JP2017017451A - Terminal device, pdn (packet data network) gateway device and communication control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication control method using a multiaccess PDN (Packet Data Network) connection on the basis of NBIFOM (Network-based IP Flow Mobility).SOLUTION: A terminal device is configured to: store default access corresponding to a multiaccess PDN connection; receive and transmit data using a first default bearer or a second default bearer on the basis of the default access; and delete the default access if an EPS (Evolved Packet System) bearer ID received through a first access network is information to identify the first default bearer or the second default bearer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a terminal device, a PDN (Packet Data Network) gateway device, and a communication control method.

  In 3GPP (The 3rd Generation Partnership Project), which conducts standardization activities of mobile communication systems in recent years, specifications of EPS (Evolved Packet System) described in Non-Patent Document 1 that realizes all-IP implementation are performed. EPS is a mobile communication system for mobile communication service providers to provide mobile phone services, and is an access network based on a core network called EPC (Evolved Packet Core) or a wireless communication standard called LTE (Long Term Evolution). Etc. are configured.

  Further, NBIOM (Network-based IP Flow Mobility) is being studied in the specification of 3GPP EPS (Non-patent Document 1). NBIOM is a technical item for the purpose of allowing a single device to simultaneously use a 3GPP interface and an interface other than 3GPP (for example, WLAN).

  Conventionally, a single PDN (Packet Data Network) connection has a communication path via any one access network of a 3GPP access network (for example, LTE access network) and an access network other than 3GPP (for example, a WLAN access network) or A bearer or transfer path is accommodated.

  NBIOM can maintain a state in which a bearer or communication path or transfer path via 3GPP and a bearer or communication path or transfer path other than 3GPP are simultaneously accommodated in one PDN connection. Such a PDN connection is a multi-access PDN connection.

  Each device included in the terminal device, the core network, and the access network uses the NBIOM function to transmit and receive data using a communication path through an appropriate access network for each application. The establishment method and the communication control method using the multi-access PDN connection are examined.

3GPP TR 23.861 Technical Specification Group Services and System Aspects, Network based IP flow mobility (Release 13)

  NBIOM does not specify a detailed procedure for establishing a multi-access PDN connection.

  More specifically, a method for selecting and transmitting a bearer associated with a multi-access PDN connection has not been clarified. For example, the details of the setting of default access associated with the multi-access PDN connection used for selecting a bearer and / or the data transmission / reception method using the default access are not clear.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a means for realizing suitable communication control for a multi-access PDN connection.

  A terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network, and a multi-access PDN (Packet Data Network) ) A control unit that establishes a connection, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection. A storage unit for storing a default access, which is information indicating one access network or a second access network, and a first default bearer or a second default bearer based on the default access. The transceiver unit receives an EPS bearer context deactivation request message including at least the EPS bearer ID via the first access network, and the control unit receives the EPS bearer ID as the first one. In the case of information identifying one default bearer or second default bearer, the default access is deleted.

  A terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network, and a multi-access PDN (Packet Data Network) ) A control unit that establishes a connection, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection. A storage unit for storing a default access, which is information indicating one access network or a second access network, and a first default bearer or a second default bearer based on the default access. A transmission / reception unit that receives and transmits an INFORMATIONAL request message or an INFORMATION response message including at least a PDN connection ID via the second access network. If the information identifies an access PDN connection, the default access is deleted.

  A terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network, and a multi-access PDN (Packet Data Network) ) A control unit that establishes a connection, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection. A storage unit for storing a default access, which is information indicating one access network or a second access network, and a first default bearer or a second default bearer based on the default access. A transmission / reception unit for transmitting / receiving data, the transmission / reception unit receives a detach request message or a detach acceptance message via the first access network, and the control unit is based on reception of the detach request message or the detach acceptance message. It is characterized by deleting default access.

  A PDN (Packet Data Gateway) gateway apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network. A control unit that establishes an access PDN (Packet Data Network) connection, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is associated with a multi-access PDN connection. Based on the default access and the storage unit for storing the default access which is the information indicating the first access network or the second access network. The default bearer or the second default bearer has a transmission / reception unit that performs data transmission / reception, the transmission / reception unit receives a session deletion request message or a session deletion response message including at least a PDN connection ID, and the control unit has a PDN connection When the ID is information for identifying a multi-access PDN connection, the default access is deleted.

  The communication control method for a terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network. (Packet Data Network) connection is established, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection, Data transmission / reception is performed using the first default bearer or the second default bearer based on the default access default access which is information indicating the first access network or the second access network. When an EPS bearer context deactivation request message including at least an EPS bearer ID is received via the first access network, and the EPS bearer ID is information for identifying the first default bearer or the second default bearer Is characterized by deleting the default access.

  The communication control method for a terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network. (Packet Data Network) connection is established, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection, Data transmission / reception is performed using the first default bearer or the second default bearer based on the default access which is information indicating the first access network or the second access network, and at least the PDN When an INFORMATIONAL request message or an INFORMATION response message including a connection ID is received via the second access network, and the PDN connection ID is information for identifying a multi-access PDN connection, the default access is deleted. Features.

  The communication control method for a terminal apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to connect to a second access network. (Packet Data Network) connection is established, the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is information associated with a multi-access PDN connection, Based on the default access which is information indicating the first access network or the second access network, data transmission / reception is performed using the first default bearer or the second default bearer, and the detach request message is transmitted. The chromatography di- or detach accept message received via the first access network, and deletes the default access based on receipt of the detach request message or the detach accept message.

  A communication control method for a PDN (Packet Data Gateway) gateway apparatus according to the present invention establishes a first default bearer to connect to a first access network, and establishes a second default bearer to establish a second access network. A multi-access PDN (Packet Data Network) connection is established, and the first access network is a 3GPP access network, the second access network is an Untrusted Non-3GPP access network, and is associated with the multi-access PDN connection Based on the default access which is the information indicating the first access network or the second access network. Data is transmitted / received using a default bearer, and a session deletion request message or a session deletion response message including at least a PDN connection ID is received. If the PDN connection ID is information for identifying a multi-access PDN connection, the default access is deleted. It is characterized by that.

  According to the present invention, data transmission / reception using a multi-access PDN connection can be realized.

It is a figure for demonstrating the outline of a mobile communication system. It is a figure for demonstrating the structure etc. of an IP mobile communication network. It is a figure for demonstrating the function structure of TWAG. It is a figure for demonstrating the structure of the memory | storage part of TWAG. It is a figure for demonstrating the function structure of HSS. It is a figure for demonstrating the structure of the memory | storage part of HSS. It is a figure for demonstrating the function structure of UE. It is a figure for demonstrating the structure of the memory | storage part of UE. It is a figure for demonstrating the function structure of PGW. It is a figure for demonstrating the structure of the memory | storage part of PGW. It is a figure for demonstrating the function structure of PCRF. It is a figure for demonstrating the structure of the memory | storage part of PCRF. It is a figure for demonstrating the function structure of ePDG. It is a figure for demonstrating the structure of the memory | storage part of ePDG. It is a figure for demonstrating the context for every bearer in the 1st example of transmission / reception of user data. It is a figure for demonstrating the context for every bearer in the 2nd example of transmission / reception of user data. It is a figure for demonstrating the context for every bearer in the 3rd example of transmission / reception of user data. It is a figure for demonstrating the PDN connection disconnection procedure (WLAN access network) of UE initiative. It is a figure for demonstrating the network initiative PDN connection disconnection procedure (WLAN access network). It is a figure for demonstrating the PDN connection disconnection procedure (3GPP access network) of UE initiative. It is a figure for demonstrating the network initiative PDN connection disconnection procedure (3GPP access network). It is a figure for demonstrating the PDN connection disconnection procedure (3GPP access network) of UE initiative. It is a figure for demonstrating the network initiative PDN connection disconnection procedure (3GPP access network). It is a figure for demonstrating the PDN connection disconnection procedure (WLAN access network) of UE initiative. It is a figure for demonstrating the network initiative PDN connection disconnection procedure (WLAN access network).

[1. First Embodiment]
Hereinafter, a wireless communication technique according to an embodiment of the present invention will be described in detail with reference to the drawings.

[1.1. System overview]
FIG. 1 is a diagram for explaining the outline of a mobile communication system in the present embodiment. As shown in the figure, the mobile communication system 9 includes a mobile terminal apparatus UE_A10, an LTE base station eNB_A45 included in the access network A, a gateway TWAG (Trusted WLAN Access Gateway) _A74 included in the access network B, and a core network. _A90 includes MME (Mobility Management Entity) _A40, SGW (Serving Gateway) 35, and PGW (PDN Gateway) _A30.

  Here, UE_A10 should just be a mobile terminal device and may be UE (User equipment), ME (Mobile equipment) or MS (Mobile Station).

  The access network A may be an LTE access network, and the eNB_A45 included in the access network A may be an LTE radio base station. The access network A may include a plurality of radio base stations. Note that the LTE access network may be E-UTRAN (Evolved Universal Terrestrial Radio Access Network). Alternatively, the access network A may be UTRAN (Universal Terrestrial Radio Access Network) or GERAN (GSM EDGE Radio Access Network).

  The access network B may be a WLAN (Wireless LAN) access network. The TWAG_A 74 may be a gateway that connects between the core network_A 90 and the WLAN access network that is connected to the PGW_A 30 in the core network_A 90.

  In this embodiment, the UE_A 10 can establish a PDN connection using an EPS bearer via the access network A.

  Moreover, UE_A10 can establish a PDN connection using the GTP / PMIPv6 transfer path between PGW_A30 and UE_A10. Note that the transfer path may be a bearer.

  Here, the core network_A 90 is an IP mobile communication network operated by a mobile communication operator (Mobile Operator).

  For example, the core network_A90 may be a core network_A90 for a mobile communication operator that operates and manages the mobile communication system 9, or a core for a virtual mobile communication operator such as MVNO (Mobile Virtual Network Operator). Network_A90 may be sufficient.

  The MME_A 40 is a control device that performs location management and access control of the UE_A 10 via the access network A. Details of the MME_A 40 will be described later.

  SGW_A 35 is a gateway device between the core network_A 90 and the access network A, and transfers user data between the UE_A 10 and the PGW_A 30.

  The PGW_A 30 is a packet data service network (PDN) gateway device that provides a communication service to the UE_A 10.

  In the present embodiment, the UE_A 10 can establish a first PDN connection and / or a second PDN connection.

  In the present embodiment, NBIOM is a technology that can establish a multi-access PDN connection.

  In this embodiment, the multi-access PDN connection is a PDN connection that can accommodate a communication path and / or bearer by 3GPP access and / or WLAN access in one PDN connection. In other words, the multi-access PDN connection can accommodate both 3GPP access and communication path via WLAN access. Note that the multi-access PDN connection may be a PDN connection that accommodates only bearers via 3GPP access, or may be a PDN connection that accommodates only transfer paths via WLAN access. In other words, the multi-access PDN connection is a PDN connection that can form one or a plurality of communication paths.

  In this embodiment, in order to clearly distinguish from a PDN connection established based on IFOM (IP Flow Mobility), a PDN connection that can select a communication path of a specific flow based on NBIOM is a multi-access PDN connection.

  The IFOM is a technology for switching a communication path of a specific IP flow using a DSMIPv6 (Dual Stack Mobile IPv6) protocol. In the present embodiment, a communication path of a specific IP flow is based on the IFOM. A PDN connection that can be switched is described as a PDN connection for IFOM.

  Further, the first PDN connection may be the multi-access PDN connection described above.

  Specifically, the first PDN connection is a PDN connection that can use the communication path EPS bearer via the access network A and the communication path using the GTP / PMIPv6 tunnel via the access network B as one PDN connection. . That is, this PDN connection can transmit and receive data via 3GPP access, WLAN access, or both accesses. The first PDN connection may be a multi-access PDN connection.

  Further, the second PDN connection may be a conventional PDN connection instead of the multi-access PDN connection. Note that the second PDN connection may be a single access PDN connection.

  Here, unlike the multi-access PDN connection, the single-access PDN connection is a single PDN connection configured only by a communication path of either 3GPP access or WLAN access. Specifically, the single access PDN connection is a PDN connection established by conventional attachment.

  That is, the second PDN connection is a PDN connection constituted by an EPS bearer via the access network A or a PDN connection constituted by a GTP / PMIPv6 transfer path via the access network B. The second PDN connection accommodates a transfer path and / or communication path via one of the access networks.

  As described above, the single access PDN connection is a PDN connection different from the multi-access PDN connection and the PDN connection for IFOM. Further, the single access PDN connection is a PDN connection different from a PDN connection for LIPA (Local IP Access). Here, LIPA is communication control for performing offload to a home network. More specifically, the base station to which the terminal device is connected performs offload by transmitting user data delivered via the conventional core network_A 90 to the home network to which the base station is connected. A PDN connection for LIPA is a PDN connection for performing communication based on such LIPA.

  Next, a configuration example of the core network_A90 will be described. FIG. 2A shows an example of the configuration of the IP mobile communication network 5. As shown in FIG. 2 (a), the core network_A90 includes HSS (Home Subscriber Server) _A50, AAA (Authentication, Authorization, Accounting) _A55, PCRF (Policy and Charging Rules FuncG) Gateway) _A65, SGW_A35, MME_A40, and SGSN (Serving GPRS Support Node) _A45.

  The core network_A90 can be connected to a plurality of radio access networks (LTE AN_A80, WLAN ANb75, WLAN ANa70, UTRAN_A20, GERAN_A25).

  The radio access network may be configured by a plurality of different access networks, or may be configured by any one access network. Furthermore, UE_A 10 can be wirelessly connected to the radio access network.

  Further, the access networks connectable with the WLAN access system are the WLAN access network b (WLAN ANb75) connected to the core network_A90 via the ePDG_A65, and the WLAN access network a (WLAN ANa70) connected to the PGW_A30, PCRF_A60, and AAA_A55. And can be configured.

  In addition, since each apparatus is comprised similarly to the conventional apparatus in the mobile communication system using EPS, detailed description is abbreviate | omitted. Hereinafter, each device will be briefly described.

  The PGW_A 30 is connected to the PDN_A 100, the SGW_A 35, the ePDG_A 65, the WLAN ANa 70, the PCRF_A 60, and the AAA_A 55, and is a relay device that transfers user data as a gateway device of the PDN_A 100 and the core network_A 90.

  The SGW_A 35 is connected to the PGW_A 30, the MME_A 40, the LTE AN_A 80, the SGSN_A 45, and the UTRAN_A 20. It is.

  The MME_A 40 is connected to the SGW_A 35, the LTE AN_A 80, and the HSS_A 50, and is an access control device that performs location information management and access control of the UE_A 10 via the LTE AN_A 80. In addition, the core network_A 90 may include a plurality of location management devices. For example, a location management device different from the MME_A 40 may be configured. A location management device different from the MME_A 40 may be connected to the SGW_A 35, the LTE AN_A 80, and the HSS_A 50 in the same manner as the MME_A 40.

  Further, when a plurality of MMEs are included in the core network_A90, the MMEs may be connected. Thereby, transmission / reception of the context of UE_A10 may be performed between MMEs.

  The HSS_A50 is connected to the MME_A40 and AAA_A55, and is a management node that manages subscriber information. The subscriber information of the HSS_A50 is referred to when the access control of the MME_A40 is performed, for example. Further, the HSS_A50 may be connected to a location management device different from the MME_A40.

  AAA_A55 is connected to PGW_A30, HSS_A50, PCRF_A60, and WLAN ANa70, and performs access control of UE_A10 connected via WLAN ANa70.

  The PCRF_A 60 is connected to the PGW_A 30, the WLAN ANa 70, the AAA_A 55, and the PDN_A 100, and performs QoS management for data delivery. For example, the QoS of the communication path between UE_A10 and PDN_A100 is managed.

  The ePDG_A 65 is connected to the PGW_A 30 and the WLAN ANb 75, and delivers user data as a gateway device between the core network_A 90 and the WLAN ANb 75.

  SGSN_A45 is connected to UTRAN_A20, GERAN_A25, and SGW_A35, and is a control device for location management between a 3G / 2G access network (UTRAN / GERAN) and an LTE access network (E-UTRAN). Furthermore, SGSN_A45 has a selection function of PGW_A30 and SGW_A35, a time zone management function of UE_A10, and a selection function of MME_A40 at the time of handover to E-UTRAN.

  Further, as shown in FIG. 2B, each radio access network includes devices (for example, base station devices and access point devices) to which the UE_A 10 is actually connected. As a device used for connection, a device adapted to a radio access network can be considered.

  In this embodiment, LTE AN_A80 may be E-URAN comprised including eNB_A45. eNB_A45 is a radio base station to which UE_A10 is connected in the LTE access system, and LTE AN_A80 may be configured to include one or a plurality of radio base stations.

  The WLAN ANa 70 includes a WLAN APa 72 and a TWAG_A 74. The WLAN APa 72 is a WLAN access system that is reliable for the operator operating the core network_A 90 and is a radio base station to which the UE_A 10 is connected. The WLAN ANa 70 includes one or more radio base stations. Also good. TWAG_A 74 is a gateway device of the core network_A 90 and the WLAN ANa 70. Further, the WLAN APa 72 and the GW 74 may be configured by a single device.

  Even when the business operator operating the core network_A 90 and the business operator operating the WLAN ANa 70 are different, such a configuration can be realized by contracts and contracts between the business operators.

  The WLAN ANb 75 includes a WLAN APb 76. The WLAN APb 76 is a radio base station to which the UE_A 10 is connected in the WLAN access system when a trust relationship is not established with the operator operating the core network_A 90, and the WLAN ANb 75 includes one or more radio base stations. May be configured.

  In this way, the WLAN ANb 75 is connected to the core network_A 90 using the ePDG_A 65 that is a device included in the core network_A 90 as a gateway. The ePDG_A 65 has a security function for ensuring the safety of communication.

  Note that WLAN ANa 70 may be distinguished as Trusted Access, and WLAN ANb 75 may be distinguished as Untrusted Access. Thereby, the presence or absence of the reliability with respect to a communication carrier can be clarified.

  Note that the WLAN ANa 70 may be classified as a trusted access network, and the WLAN ANb 75 may be classified as an untrusted access network. Thereby, the presence or absence of reliability with respect to the communication carrier of the access network can be clarified.

  Note that WLAN ANa 70 may be classified as Trusted Non-3GPP Access, and WLAN ANb75 may be classified as Untrusted Non-3GPP Access. As a result, it is possible to clarify whether or not the communication carrier has reliability, and to clarify that the WLAN is an access different from the 3GPP access such as LTE.

  Note that WLAN ANa 70 may be classified as Trusted Non-3GPP Access Network, and WLAN ANb75 may be classified as Untrusted Non-3GPP Access Network. As a result, it is possible to clarify whether or not the access network carrier is reliable and to clarify that the WLAN is an access different from the 3GPP access such as LTE.

  The UTRAN_A 20 includes an RNC (Radio Network Controller) _A 24 and an eNB (UTRAN) _A 22. eNB (UTRAN) _A22 is a radio base station to which UE_A10 is connected by UTRA (UMTS Terrestrial Radio Access), and UTRAN_A20 may include one or a plurality of radio base stations. The RNC_A 24 is a control unit that connects the core network_A 90 and the eNB (UTRAN) _A 22, and the UTRAN_A 20 may be configured to include one or a plurality of RNCs. The RNC_A 24 may be connected to one or more eNBs (UTRAN). Furthermore, RNC_A24 may be connected to a radio base station (BSS (Base Station Subsystem) _A26) included in GERAN_A25.

  GERAN_A25 includes BSS_A26. The BSS_A 26 is a radio base station to which the UE_A 10 is connected by GERA (GSM / EDGE Radio Access), and the GERAN_A 25 may be configured by one or a plurality of radio base stations BSS. A plurality of BSSs may be connected to each other. The BSS_A 26 may be connected to the RNC_A 24.

  In this specification, the UE_A 10 being connected to each radio access network means being connected to a base station device, an access point, etc. included in each radio access network. Also via a base station device or access point.

[1.2. Device configuration]
Hereinafter, the configuration of each apparatus will be described.

[1.2.1. TWAG configuration]
FIG. 3 shows a device configuration of the TWAG_A 74. As shown in the figure, the TWAG_A 74 includes a network connection unit_A320, a control unit_A300, and a storage unit_A340. The network connection unit_A320 and the storage unit_A340 are connected to the control unit_A300 via a bus.

  The control unit_A300 is a functional unit for controlling the TWAG_A74. The control unit_A300 implements various processes by reading and executing various programs stored in the storage unit_A340.

  The network connection unit_A320 is a data transmission / reception unit that transmits / receives user data and / or control messages, and the TWAG_A74 is a functional unit for connecting to the PGW_A30. The network connection unit_A320 may include a transmission unit and a reception unit.

  The storage unit_A340 is a functional unit that stores programs, data, and the like necessary for each operation of the TWAG_A74. The storage unit_A340 is configured by, for example, a semiconductor memory, an HDD (Hard Disk Drive), or the like.

  As illustrated in FIG. 3, the storage unit_A340 stores TWAG capability_A342, Network capability_A344, and EPS bearer context_A346. Hereinafter, the information element memorize | stored in memory | storage part_A340 is demonstrated.

  FIG. 4 shows information elements stored in the storage unit_A340. FIG. 4A shows an example of TWAG capability_A 342 stored in TWAG_A 74. TWAG capability_A 342 may store identification information (NBIFOM Capability) indicating whether the ability to establish the first PDN connection is supported for each TWAG. In other words, TWAG capability_A 342 may be identification information indicating whether or not TWAG_A 74 supports the NBIOM function.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. That is, it may mean that the TWAG_A 74 is a gateway having a function of establishing the first PDN connection by the presence of NBIOM capability in the storage unit. In other words, the presence of the NBIOM capability in the storage unit_A340 may mean that the TWAG_A74 is a gateway that supports the NBIOM function. Specifically, NBIOM Capability may include “allowed” or “Not allowed”.

  As shown in FIG. 4A, the NBIOM capability may be stored in association with the identification information TWAG ID of TWAG_A74. When not associated with a TWAG ID, NBIOM Capability may mean the ability of TWAG_A 74 to store.

  When TWAG ID and NBIOM capability are stored in association with each other, TWAG_A 74 may store TWAG capabilities of a plurality of TWAGs.

  In this case, when the UE_A 10 performs handover to another TWAG, the TWAG_A 74 may select the handover destination TWAG based on the TWAG capability_A 342.

  Next, Network capability_A344 will be described. FIG. 4B shows an example of Network capability_A344 stored in TWAG_A74. Network capability_A 344 stores NBIOM capability for each network, that is, for each PGW.

  Here, NBIOM capability is identification information indicating whether or not the ability to establish the first PDN connection is supported for each network. In other words, the identification information indicates whether or not the PGW_A 30 supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the NBIOM capability may be identification information indicating a gateway that supports the NBIOM function. That is, it may mean that the PGW_A 30 is a gateway having a function of establishing the first PDN connection because the NBIOM capability exists in the storage unit_A300. In other words, the presence of NBIOM capability in the storage unit_A300 may mean that the PGW_A30 is a gateway that supports the NBIOM function.

  As shown in FIG. 4B, the TWAG_A 74 may store NBIOM capability in association with the PGW ID. Further, as shown in the figure, each NGIFOM capability may be stored in association with a plurality of PGWs.

  The PGW ID may be information for identifying the PGW, and may be, for example, an APN (Access Point Name).

  Next, the EPS bearer context_A 346 will be described. The EPS bearer context_A 346 may be classified into an EPS bearer context for each UE stored for each UE, an EPS bearer context and a bearer for each PDN connection, and / or an EPS bearer context for each transfer path.

  FIG.4 (c) shows the information element contained in the EPS bearer context for every UE. As can be seen from the figure, the TWAG_A 74 stores UE NBIOM capability and NBIOM allowed for each UE.

  The UE NIFOM capability is the NBIOM capability of the UE. The UE NIFOM capability is identification information indicating whether or not the capability of establishing a first PDN connection is supported for each UE. In other words, the UE NBIOM capability is identification information indicating whether or not the UE supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in the UE NIFOM Capability.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Or UE NIFOM capability may be the identification information which shows that UE has the capability to establish a 1st PDN connection. That is, it may mean that the UE has a function of establishing the first PDN connection by the presence of UE NBIOM capability.

  In other words, the identification information may indicate that the UE supports the NBIOM function. That is, it may mean that the UE supports the NBIOM function by the presence of UE NBIOM capability in the storage unit.

  NBIOM allowed is identification information indicating an APN that is permitted to establish a PDN connection using the NBIOM. NBIOM may be associated with at least APN. NBIOM allowed may be associated with a plurality of APNs.

  In this embodiment, APN1 is associated with NBIOM allowed. That is, APN1 is allowed to establish a multi-access PDN connection. In other words, in this embodiment, UE_A 10 is permitted to establish a multi-access PDN connection using APN1. Note that APN1 is allowed to establish a conventional PDN connection instead of a multi-access PDN connection.

  Further, in the present embodiment, APN2 is not associated with NBIOM allowed. That is, in this embodiment, the APN 2 is not permitted to establish a multi-access PDN connection. That is, in this embodiment, UE_A10 cannot establish a multi-access PDN connection using APN2.

  NBIOM allowed may be stored before the PDN connection is established.

  The TWAG_A 74 may access the HSS_A 50 to acquire NBIOM allowed before and / or during the establishment procedure of the PDN connection.

  Moreover, the identification information of UE may be contained in the EPS bearer context for every UE. The identification information of the UE may be IMSI.

  FIG. 4D shows an EPS bearer context for each PDN connection. The EPS bearer context for each PDN connection includes a PDN connection ID, a network allowed mode, an operation mode, a user plane connection ID, a TWAG MAC address, and a NBIOM permission (included).

  The PDN connection ID is identification information for identifying a PDN connection. In the present embodiment, UE_A10, TWAG_A74, and PGW_A30 may store the same PDN connection ID.

  The operation mode is a mode indicating whether the UE or the network can initiate data transmission or communication control when the PDN connection identified by the PDN connection ID is the first PDN connection. Identification information.

  More specifically, for example, the operation mode in which communication control can be started from the UE may be a UE initiated mode.

  Further, the operation mode that can start communication control from the network and / or the PGW_A 30 and / or the PCRF_A 60 may be a network initiated mode.

  Network allowed mode indicates an operation mode permitted by the network. The network allowed mode may include a UE initiated mode, a network initiated mode, or both.

  User plane connection ID is identification information for identifying a connection used for transmission of user data when a UE establishes a communication path via TWAG_A74.

  TWAG MAC address is a physical address of TWAG.

  The NBIOM permission is information indicating that the PDN connection established by the PDN connection ID has established a multi-access PDN connection. In other words, NBIOM permission indicates that the first PDN connection has been established.

  That is, the TWAG_A 74 stores the NBIOM permission, which means that this PDN connection is the first PDN connection.

  NBIOM permission is identification information stored in the TWAG_A 74 when a PDN connection is established.

  The TWAG_A 74 may access the HSS_A 50 and acquire the NBIOM permission while the PDN connection is established. Alternatively, based on the establishment of the multi-access PDN connection, the TWAG_A 74 may store the NBITOM permission.

  Next, an EPS bearer context for each bearer and / or transfer path will be described. As shown in FIG. 4E, the EPS bearer context for each bearer and / or transfer path may include transfer path identification information and Routing Rule.

  The transfer path identification information is information for identifying a transfer path and / or a bearer. The transfer path identification information may be an EPS bearer ID, for example.

  Routing Rule indicates a correspondence between the Routing Filter and the Routing address or Routing access type. Based on this association, it is determined whether to use a communication path via a 3GPP access network or a communication path via a WLAN access network.

  Here, Routing access type indicates an access network through which the flow passes. For example, this indicates 3GPP or WLAN.

  Also, Routing address indicates an IP address that can be routed. For example, the IP address of SGW_A35 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, it may be an IP address of MAG (Mobile Access Gateway).

  The Routing Rule may be notified from the PGW or PCRF_A 60 or may be notified from the UE_A 10. Alternatively, the value stored in advance as a default value by the TWAG_A 74 may be used.

  The IP flow may be switched by including an IP header in the Routing Filter. Alternatively, the flow may be switched for each application by including the application ID in the Routing Filter. Alternatively, a TFT may be included.

  A plurality of rules may be stored in the Routing Rule. Further, the routing rule may include a priority order in each rule.

  TWAG capability and Network capability may be included in EPS bearer context_A346.

[1.2.2. HSS configuration]
Next, the configuration of the HSS_A50 will be described. FIG. 5 shows an apparatus configuration of the HSS_A50. As shown in the figure, the HSS_A50 includes a network connection unit_A520, a control unit_A500, and a storage unit_A540. The network connection unit _A 520 and the storage unit _A 540 are connected to the control unit _A 500 via a bus.

  The control unit_A500 is a functional unit for controlling the HSS_A50. The control unit _A 500 implements various processes by reading and executing various programs stored in the storage unit _A 540.

  The network connection unit_A 520 is a data transmission / reception unit that transmits / receives user data and / or control messages, and the HSS_A 50 is a functional unit for connecting the MME_A 40 and / or other MMEs to the AAA_A 55. The network connection unit _A 520 may include a transmission unit and a reception unit.

  The storage unit_A540 is a functional unit that stores programs, data, and the like necessary for each operation of the HSS_A50. The storage unit_A 540 includes, for example, a semiconductor memory, an HDD (Hard Disk Drive), or the like.

  As illustrated in FIG. 5, the storage unit _A 540 stores HSS data _A 542. Hereinafter, the information element memorize | stored in memory | storage part_A540 is demonstrated.

  FIG. 6 shows information elements stored in the storage unit_A540. FIG. 6A shows an example of HSS data for each UE stored in the HSS_A 50.

  As shown in the figure, the HSS data for each UE includes IMSI, MSISDN, IMEI / IMEISV, Access Restriction, UE NFIOM Capability, and NBIOM allowed.

  IMSI is identification information assigned to a user (subscriber) who uses the UE.

  MSISDN represents the phone number of the UE.

  IMEI / IMISV is identification information assigned to the UE.

  Access Restriction indicates registration information for access restriction.

  UE NBIOM capability indicates the NBIOM capability of the UE. The UE NIFOM capability is identification information indicating whether or not the capability of establishing a first PDN connection is supported for each UE. In other words, it indicates whether or not the UE supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Or UE NIFOM capability may be the identification information which shows that UE has the capability to establish a 1st PDN connection. That is, it may mean that the UE has a function of establishing the first PDN connection by the presence of UE NBIOM capability.

  NBIOM allowed is identification information indicating an APN that is permitted to establish a PDN connection using the NBIOM. The NBIOM may be associated with at least the APN. NBIOM allowed may be associated with a plurality of APNs.

  In this embodiment, APN1 is associated with NBIOM allowed. That is, APN1 is allowed to establish a multi-access PDN connection. In other words, in this embodiment, UE_A 10 is permitted to establish a multi-access PDN connection using APN1. Note that APN1 is allowed to establish a conventional PDN connection instead of a multi-access PDN connection.

  Further, in the present embodiment, APN2 is not associated with NBIOM allowed. That is, in this embodiment, the APN 2 is not permitted to establish a multi-access PDN connection. That is, in this embodiment, UE_A10 cannot establish a multi-access PDN connection using APN2.

  NBIOM allowed may be stored before the PDN connection is established.

  FIG. 6B shows an example of HSS data for each PDN connection stored in the HSS_A 50. As can be seen from the figure, the HSS data for each PDN connection includes at least Context ID, PDN address, PDN Type, APN (Access Point Name), WLAN offset availability, PDN GW ID, and NBIOM permission.

  Context ID is context identification information for storing HSS data for each PDN connection.

  PDN Address indicates a registered IP address. PDN Address is the IP address of UE_A10.

  PDN Type indicates the type of PDN Address. That is, for example, identification information for identifying IPv4, IPv6, or IPv4v6.

  The APN is a label indicating the access destination of the network in accordance with the DNS naming rule.

  The WLAN offload ability is identification information indicating whether the traffic connected by this APN can be offloaded to the WLAN using the cooperation function between the WLAN and 3GPP or the 3GPP connection is maintained. The WLAN offload ability may be divided for each RAT type. Specifically, it may be different between LTE (E-UTRA) and 3G (UTRA).

  The PDN GW identity is identification information for identifying the PGW used in this APN. This identification information may be FQDN (Fully Qualified Domain Name) or an IP address.

  NBIOM permission is information indicating that this PDN connection has established a multi-access PDN connection. In other words, NBIOM permission indicates that the first PDN connection has been established.

  That is, the TWAG_A 74 stores the NBIOM permission, which means that this PDN connection is the first PDN connection.

  NBIOM permission is identification information stored in the TWAG by establishing a PDN connection.

  Specifically, for example, NBIOM permission is included in the HSS data for each PDN connection including APN1, and NBIOM permission may not be included in the HSS data for each PDN connection including APN2.

  In other words, the PDN connection by APN1 may be the first PDN connection, and APN2 should not be the first PDN connection.

[1.2.3. UE configuration]
Next, the configuration of UE_A 10 will be described. FIG. 7 shows a device configuration of the UE_A 10. As shown in the figure, the UE_A 10 includes an LTE interface unit_A 720, a WLAN interface unit_A 740, a control unit_A 700, and a storage unit_A 750.

  The LTE interface unit _A 720, the WLAN interface unit _A 740, and the storage unit _A 750 are connected to the control unit _A 700 via a bus.

  The control unit_A700 is a functional unit for controlling the UE_A10. The control unit _A 700 implements various processes by reading and executing various programs stored in the storage unit _A 750.

  The LTE interface unit _A 720 is a data transmission / reception unit that transmits and receives user data and / or control messages, and is a functional unit for the UE_A 10 to connect to the LTE base station and to connect to the IP access network. An external antenna 710 is connected to the LTE interface unit_A720. The LTE interface unit _A 720 may include a transmission unit and a reception unit.

  The WLAN interface unit _A 740 is a data transmitting / receiving unit that transmits and receives user data and / or control messages, and is a functional unit for the UE_A 10 to connect to the WLAN AP and to connect to the IP access network. An external antenna 730 is connected to the WLAN interface unit_A740.

  The control unit_A700 is a functional unit for controlling the UE_A10. The control unit _A 700 implements various processes by reading and executing various programs stored in the storage unit _A 750.

  The storage unit 740 is a functional unit that stores programs, data, and the like necessary for each operation of the UE_A 10. The storage unit_A 750 is configured by, for example, a semiconductor memory, an HDD (Hard Disk Drive), or the like.

  As illustrated in FIG. 7, the storage unit _A 750 stores the UE context _A 752. Hereinafter, the information element memorize | stored in memory | storage part_A750 is demonstrated. UE context_A 752 is classified into a UE context for each UE, a UE context for each PDN connection, and a UE context for each transfer path and / or bearer. The UE context for each transfer path and / or bearer may be configured with a UE context for each Default Bearer and a UE context for each Dedicated Bearer.

  FIG. 8A is an example of a UE context stored for each UE. As shown in the figure, the UE context for each UE includes IMSI, EMM State, GUTI, ME Identity, and UE NBIOM capability.

  IMSI is identification information assigned to a user (subscriber) who uses UE_A10.

  EMM State indicates the mobility management state of UE_A10. For example, EMM-REGISTRED (registered state, registered state) in which UE_A 10 is registered in the network, or EMM-DEREGISTERD (unregistered state, registered state) in which UE_A 10 is not registered in the network may be used.

  GUTI is an abbreviation for Globally Unique Temporary Identity, and is temporary identification information of UE_A10. GUTI includes MME_A 40 identification information (GUMMEI: Globally Unique MME Identifier) and UE_A 10 identification information (M-TMSI) in the specific MME_A 40.

  ME Identity is an ID of the ME, and may be, for example, IMEI / IMISV.

  UE NBIOM capability is NBIOM capability of UE_A10. The UE NIFOM capability is identification information indicating whether or not the capability of establishing a first PDN connection is supported for each UE. In other words, the UE NIFOM capability is identification information indicating whether the NBIOM function is supported for each UE. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  The NBIOM function may be information indicating that a function capable of establishing a multi-access PDN connection is provided.

  Alternatively, the UE NIFOM capability may be identification information indicating that the UE_A 10 has the ability to establish a first PDN connection. That is, it may mean that UE_A10 has a function of establishing a first PDN connection by the presence of UE NBIOM capability in the storage unit of UE_A10.

  In other words, the UE NIFOM capability may be identification information indicating that the UE_A 10 supports the NBIOM function. That is, it may mean that UE_A10 supports the NBIOM function when UE NBIF capability exists in storage unit_A750 of UE_A10.

  Further, the UE_A 10 can establish one or a plurality of PDN connections. UE_A10 may memorize | store the information matched with the PDN connection for every PDN connection. An example of the UE context for each PDN connection is shown using FIG.

  As shown in the figure, the UE context for each PDN connection includes at least a PDN connection ID, an APN in Use, an IP address, a WLAN offload ability, a UE allowed mode, an Operation mode, and a Default Bearer. Further, a default access (Default Access) may be included in the UE context for each PDN connection.

  The PDN connection ID is identification information for identifying a PDN connection. UE_A10, TWAG_A74, and PGW_A30 may store the same identification information.

  APN in Use is the APN used immediately before by UE_A 10. The APN may include network identification information and default operator identification information.

  The IP address is an IP address assigned to the UE_A 10 by the PDN connection, and may be an IPv4 address or an IPv6 prefix.

  WLAN offloadability indicates whether communication associated with the PDN connection is allowed to be offloaded to the WLAN using the interworking function between the WLAN and 3GPP, or whether to maintain 3GPP access. Load permission information.

  UE allowed mode is an Operation mode permitted by UE_A 10. This identification information may indicate either or both of the UE initiated mode and the network initiated mode.

  When the current PDN connection is the first PDN connection, the operation mode is mode identification information indicating whether the UE_A 10 or the network can start data transmission / reception or start communication control. is there.

  Default Bearer is bearer identification information for identifying a default bearer in this PDN connection.

  Note that, when the PDN connection is a multi-access PDN connection, the UE_A 10 may establish a plurality of default bearers for the PDN connection. Therefore, a plurality of default bearers may be associated and managed for the multi-access PDN connection. Specifically, bearer identification information corresponding to each default bearer may be associated with the multi-access PDN connection and managed.

  Further, the UE_A 10 may manage the default bearer and the access network in association with each other.

  Specifically, UE_A 10 may store bearer identification information for identifying a default bearer for access network A and a default bearer for access network B. Here, the default bearer for the access network may be a default bearer for the access system of the access network. Therefore, UE_A 10 may store a default bearer for 3GPP access and a default bearer for WLAN access in association with the multi-access PDN connection.

  Further, the default bearer for the multi-access PDN may be a default bearer established by the UE_A 10. In other words, in a state where only one default bearer is established for the multi-access PDN connection, the UE_A 10 stores one default bearer for the multi-access PDN connection and two default bearers for the multi-access PDN connection. In the state in which the bearer is established, UE_A 10 may store two default bearers for the multi-access PDN connection.

  When the PDN connection is a multi-access PDN connection, the UE_A 10 may store the default bearer as a UE context for each default bearer.

  Next, default access (Default Access) may be information indicating 3GPP access or WLAN access. Here, 3GPP access may be an access system that is not WLAN access. More specifically, it may be information indicating an access network including E-UTRAN access, UTRAN access, and GERAN access.

  Alternatively, the 3GPP access may be more detailed information. For example, the 3GPP access may be an E-UTRAN access, a UTRAN access, or a GERAN access.

  When a plurality of default bearers are established, UE_A 10 may select a default bearer based on default access, and may transmit / receive user data using the selected default bearer. As described above, the default access is information associated with the access system and / or the access network, and may be information for selecting a bearer for data transmission / reception.

  Note that the UE_A 10 is used when the PDN connection is a multi-access PDN connection, or when the UE_A 10 is simultaneously connected to a plurality of access systems and establishes a communication path for the PDN connection via a plurality of access networks. The UE_A 10 may store default access for the PDN connection.

  FIG. 8C shows an example of network capability. In Network capability, the NBIOM capability for each network, that is, for each PGW is stored.

  Here, NBIOM capability is identification information indicating whether or not the ability to establish the first PDN connection is supported for each network. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the presence of NBIOM capability may mean that the PGW_A 30 and / or the network is a gateway having a function of establishing the first PDN connection.

  As illustrated in FIG. 8C, the UE_A 10 stores NBIOM capability in association with the PGW ID. Further, NBIOM capability may be stored in association with a plurality of PGWs.

  The PGW ID is information for identifying the PGW_A 30. The PGW ID may be an APN, for example.

  TWAG capability is shown in FIG.8 (d). In TWAG capability, identification information (NBIOM Capability) indicating whether or not the ability to establish the first PDN connection is supported for each TWAG is stored. In other words, the identification information indicates whether or not TWAG_A 74 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. That is, it may mean that the TWAG_A 74 is a gateway having a function of establishing the first PDN connection by the presence of NBIOM capability in the storage unit. In other words, the presence of the NBIOM capability in the storage unit may mean that the TWAG_A 74 is a gateway that supports the NBIOM function.

  The UE_A 10 may store the NBIOM capability in association with the TWAG ID. Further, NBIOM Capabilities for a plurality of TWAGs may be stored.

  In the case of a multi-access PDN connection, UE_A 10 may store TWAG capability and Network capability in the UE context, or store TWAG capability and Network capability independently from the UE context.

  FIG. 8E shows a UE context for each default bearer. The UE context for each default bearer includes bearer identification information and access network identification information. In addition, when there are a plurality of default bearers associated with the multi-access PDN connection, there may be a plurality of UE contexts for each default bearer.

  Bearer information is information for identifying a bearer. The bearer identification information may be an EPS bearer ID, for example.

  The access network information is information for identifying the access network. The access network information may be information indicating 3GPP access or WLAN access.

  FIG. 8F shows a UE context for each Dedicated Bearer. The UE context for each Dedicated Bearer includes transfer path identification information and Routing Rule. In addition, when there are a plurality of bearers associated with the multi-access PDN connection, a plurality of UE contexts for each Dedicated Bearer may exist.

  The Routing Rule may be information including a Routing Rule identifier and / or a Routing Filter and / or a Routing Access Information and / or a Routing Rule Priority. An example of Routing Rule is shown in FIG.

  Here, the Routing Rule identifier may be information for identifying the Routing Rule associated with the PDN connection. The Routing Rule identifier may be the same information as the bearer identification information.

  The Routing Filter may be information including an IP header and / or an application ID and / or a TFT. UE_A10 may switch an IP flow by including an IP header in a Routing Filter. Or UE_A10 may switch a flow for every application by including application ID in Routing Filter. Or UE_A10 may switch an IP flow based on TFT by including TFT in Routing Filter.

  The Routing Access Information may be information indicating an access network through which the IP flow passes. For example, 3GPP or WLAN may be included in Routing Access Information. The Routing Access Information may be a Routing access type.

  The Routing Rule Priority may be information indicating the priority of the Routing Rule.

  In addition, the Routing Rule may include a Routing address. The routing address may be information indicating an IP address that can be routed. For example, the IP address of SGW_A35 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, it may be an IP address of MAG (Mobile Access Gateway).

  The Routing Rule may be notified from the PGW_A 30 or the PCRF_A 60. Or the value which UE_A10 memorized as a default value beforehand may be sufficient.

  Also, a plurality of rules (rules) may be stored in the Routing Rule. Further, the routing rule may include a priority order in each rule.

[1.2.4. PGW configuration]
Next, the configuration of the PGW_A 30 will be described. FIG. 9 shows a device configuration of the PGW_A 30. As shown in the figure, the PGW_A 30 includes a network connection unit_A 920, a control unit_A 900, and a storage unit_A 940. The network connection unit _A 920 and the storage unit _A 940 are connected to the control unit _A 900 via a bus.

  The control unit_A900 is a functional unit for controlling the PGW_A30. The control unit _A 900 implements various processes by reading and executing various programs stored in the storage unit _A 940.

  The network connection unit _A 920 is a data transmission / reception unit that transmits and receives user data and / or control messages. The PGW_A 30 is a functional unit for connecting the SGW_A 35 and / or the PCRF_A 60 and / or the ePDG_A 65 and / or the AAA_A 55 and / or the GW 74. The network connection unit _A 920 may include a transmission unit and a reception unit.

  The storage unit_A940 is a functional unit that stores programs, data, and the like necessary for each operation of the PGW_A30. The storage unit_A 940 includes, for example, a semiconductor memory, an HDD (Hard Disk Drive), and the like.

  The storage unit_A 940 stores the EPS bearer context_A 942 as illustrated in the drawing. Some EPS bearer contexts are stored for each UE, stored for each APN, stored for each PDN connection, and stored for each transfer path and / or bearer. included. The EPS bearer context for each transfer path and / or bearer may be configured of an EPS bearer context for each default bearer and an EPS bearer context for each dedicated bearer.

  First, the EPS bearer context for each UE will be described. FIG. 10A shows an example of an EPS bearer context for each UE. As shown in the figure, the EPS bearer context includes at least IMSI, ME Identity, MSISDN, and UE NBIOM Capability.

  IMSI is information for identifying the user of UE_A10.

  ME Identity is an ID of the ME, and may be, for example, IMEI / IMISV.

  MSISDN represents the telephone number of UE_A10.

  UE NBIOM capability is NBIOM capability of UE_A10. UE NIFOM capability is identification information indicating whether or not each UE has the ability to establish a first PDN connection. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Or UE NIFOM capability may be identification information which shows that UE_A10 has the capability to establish a 1st PDN connection. That is, it may mean that the UE_A 10 has a function of establishing the first PDN connection due to the presence of UE NBIOM capability.

  Further, the UE_A 10 can establish one or a plurality of PDN connections. PGW_A30 may memorize | store the information matched with the PDN connection for every PDN connection which UE_A10 establishes. An example of the EPS bearer context stored for each PDN connection will be described with reference to FIG.

  As shown in the figure, the EPS bearer context for each PDN connection includes at least a PDN connection ID, an IP address, a PDN type, an APN, a network allowed mode, and an operation mode.

  Furthermore, a default access (Default Access) may be included in the EPS bearer context for each PDN connection.

  The PDN connection ID is identification information for identifying a PDN connection. UE_A10, TWAG_A74, and PGW_A30 may store the same identification information.

  IP Address indicates an IP address to which UE_A 10 is assigned for this PDN connection. The IP address may be an IPv4 and / or IPv6 prefix.

  PDN type indicates the type of IP address. PDN type indicates, for example, IPv4, IPv6, or IPv4v6.

  The APN is a label indicating the access destination of the network in accordance with the DNS naming rule.

  Network allowed mode indicates an operation mode permitted by the network. The network allowed mode may include either UE-initiated mode or Network-initiated mode, or both.

  The operation mode is mode identification information indicating whether the UE_A 10 or the network can initiate data transmission or communication control when the current PDN connection is the first PDN connection.

  More specifically, for example, a UE initiated mode in which communication control can be started from the UE_A 10 and a network initiated mode in which communication control can be started from the network may be identified.

  Default Bearer is bearer identification information for identifying a default bearer in this PDN connection.

  Note that the PGW_A 30 may establish a plurality of default bearers for the PDN connection when the PDN connection is a multi-access PDN connection. Therefore, a plurality of default bearers may be associated and managed for the multi-access PDN connection. Specifically, bearer identification information corresponding to each default bearer may be associated with the multi-access PDN connection and managed.

  Further, the PGW_A 30 may manage the default bearer and the access network in association with each other.

  Specifically, the PGW_A 30 may store bearer identification information that identifies a default bearer for the access network A and a default bearer for the access network B. Here, the default bearer for the access network may be a default bearer for the access system of the access network. Therefore, the PGW_A 30 may store a default bearer for 3GPP access and a default bearer for WLAN access in association with the multi-access PDN connection.

  The default bearer for the multi-access PDN may be a default bearer established by the PGW_A 30. In other words, when only one default bearer is established for the multi-access PDN connection, the PGW_A 30 stores one default bearer for the multi-access PDN connection and two default bearers for the multi-access PDN connection. In the state where the bearer is established, the PGW_A 30 may store two default bearers for the multi-access PDN connection.

  If the PDN connection is a multi-access PDN connection, the PGW_A 30 may store the default bearer as an EPS bearer context for each default bearer.

  Next, default access (Default Access) may be information indicating 3GPP access or WLAN access. Here, 3GPP access may be an access system that is not WLAN access. More specifically, it may be information indicating an access network including E-UTRAN access, UTRAN access, and GERAN access.

  Alternatively, the 3GPP access may be more detailed information. For example, the 3GPP access may be an E-UTRAN access, a UTRAN access, or a GERAN access.

  When the PGW_A 30 has established a plurality of default bearers, the PGW_A 30 may select a default bearer based on the default access, and may transmit / receive user data using the selected default bearer. As described above, the default access is information associated with the access system and / or the access network, and may be information for selecting a bearer for data transmission / reception.

  Note that PGW_A30 is used when the PDN connection is a multi-access PDN connection or when the UE_A 10 is simultaneously connected to a plurality of access systems and establishes a communication path for the PDN connection via a plurality of access networks. The PGW_A 30 may store default access for the PDN connection.

  FIG. 10C shows an example of network capability. In Network capability, the NBIOM capability for each network, that is, for each PGW is stored.

  Here, NBIOM capability is identification information indicating whether or not the ability to establish the first PDN connection is supported for each network. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

The NBIOM function may be information indicating that the multi-access PDN connection is established, or the NBIOM capability is an identification indicating the ability to establish the first PDN connection. It may be information. In other words, the presence of NBIOM capability may mean that the PGW_A 30 and / or the network is a gateway having a function of establishing the first PDN connection.

  As illustrated in FIG. 10C, the PGW_A 30 stores the NBIOM capability in association with the PGW ID. Further, NBIOM capability may be stored in association with a plurality of PGWs.

  The PGW ID may be information for identifying the PGW_A 30, and may be, for example, an APN.

  FIG. 10D shows TWAG capability. In TWAG capability, identification information (NBIOM Capability) indicating whether or not the ability to establish the first PDN connection is supported for each TWAG is stored. In other words, the identification information indicates whether or not TWAG_A 74 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. That is, it may mean that the TWAG_A 74 is a gateway having a function of establishing the first PDN connection by the presence of NBIOM capability in the storage unit. In other words, the presence of the NBIOM capability in the storage unit may mean that the TWAG_A 74 is a gateway that supports the NBIOM function.

  The PGW_A 30 may store NBIOM Capability in association with the TWAG ID. Further, NBIOM Capabilities for a plurality of TWAGs may be stored.

  In the case of a multi-access PDN connection, the PGW_A 30 may store the TWAG capability and the network capability in the EPS bearer context, or may store the TWAG capability and the network capability independently from the EPS bearer context.

  FIG. 10E shows an EPS bearer context for each default bearer. The UE context for each default bearer includes bearer identification information and access network identification information. Note that when there are a plurality of default bearers associated with the multi-access PDN connection, a plurality of EPS bearer contexts may exist for each default bearer.

  Bearer information is information for identifying a bearer. The bearer identification information may be an EPS bearer ID, for example.

  The access network information is information for identifying the access network. The access network information may be information indicating 3GPP access or WLAN access.

  FIG. 10F shows an EPS bearer context for each Dedicated Bearer. The EPS bearer context for each Dedicated Bearer includes transfer path identification information and Routing Rule. When there are a plurality of bearers associated with the multi-access PDN connection, a plurality of EPS bearer contexts for each Dedicated Bearer may exist.

  The Routing Rule may be information including the Routing Filter and / or the Routing Access Information and / or the Routing Rule Priority and / or the Routing Rule identifier. An example of the Routing Rule is shown in FIG.

  Here, the Routing Rule identifier may be information for identifying the Routing Rule associated with the PDN connection. The Routing Rule identifier may be the same information as the bearer identification information.

  The Routing Filter may be information including an IP header and / or an application ID and / or a TFT. The PGW_A 30 may switch the IP flow by including an IP header in the Routing Filter. Alternatively, the PGW_A 30 may switch the flow for each application by including the application ID in the Routing Filter. Alternatively, the PGW_A 30 may switch the IP flow based on the TFT by including the TFT in the Routing Filter.

  The Routing Access Information may be information indicating an access network through which the IP flow passes. For example, 3GPP or WLAN may be included in Routing Access Information. The Routing Access Information may be a Routing access type.

  The Routing Rule Priority may be information indicating the priority of the Routing Rule.

  In addition, the Routing Rule may include a Routing address. The routing address may be information indicating an IP address that can be routed. For example, the IP address of SGW_A35 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, it may be an IP address of MAG (Mobile Access Gateway).

  The Routing Rule may be notified from the UE_A 10 or the PCRF_A 60. Or the value which PGW_A30 memorize | stored beforehand as a default value may be sufficient.

  Also, a plurality of rules (rules) may be stored in the Routing Rule. Further, the routing rule may include a priority order in each rule.

[1.2.5. PCRF configuration]
Next, the configuration of PCRF_A 60 will be described. FIG. 11 shows an apparatus configuration of PCRF_A 60. As shown in the figure, the PCRF_A 60 includes a network connection unit_A 1120, a control unit_A 1100, and a storage unit_A 1140. The network connection unit_A1120 and the storage unit_A1140 are connected to the control unit_A1100 via a bus.

  The control unit_A1100 is a functional unit for controlling the PCRF_A60. The control unit_A1100 realizes various processes by reading and executing various programs stored in the storage unit_A1140.

  The network connection unit_A 1120 is a data transmission / reception unit that transmits / receives user data and / or control messages, and is a functional unit for the PCRF_A 60 to connect to the PGW_A 30 and / or TWAG_A 74 and / or AAA_A 55. The network connection unit_A 1120 may include a transmission unit and a reception unit.

  The storage unit_A1140 is a functional unit that stores programs, data, and the like necessary for each operation of the PCRF_A60. The storage unit_A 940 includes, for example, a semiconductor memory, an HDD (Hard Disk Drive), and the like.

  The storage unit_A 1140 stores the UE context_A 1142 as shown in the figure. The UE context_A 1142 is classified into a UE context stored for each UE, a UE context stored for each PDN connection, and a UE context for each transfer path and / or bearer. The UE context for each transfer path and / or bearer may be configured with a UE context for each Default Bearer and a UE context for each Dedicated Bearer.

  FIG. 12A shows a UE context for each UE. As shown in the figure, the context includes at least a Subscriber ID and UE NBIOM Capability.

  The Subscriber ID is user identification information. For example, IMSI may be used.

  UE NBIOM capability is NBIOM capability of UE_A10. The UE NIFOM capability is identification information indicating whether or not the capability of establishing a first PDN connection is supported for each UE. In other words, UE NBIOM capability is identification information indicating whether or not UE_A 10 supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Or UE NIFOM capability may be identification information which shows that UE_A10 has the capability to establish a 1st PDN connection. That is, it may mean that the UE_A 10 has a function of establishing the first PDN connection due to the presence of UE NBIOM capability.

  In other words, the identification information may indicate that the UE_A 10 supports the NBIOM function. That is, it may mean that the UE_A 10 supports the NBIOM function due to the presence of the UE NBIOM capability in the storage unit_A 1100.

  Further, the UE_A 10 can establish one or a plurality of PDN connections. PCRF_A60 may memorize | store the information matched with the PDN connection for every PDN connection which UE_A10 establishes. An example of the UE context for each PDN connection will be described with reference to FIG. As shown in the figure, a UE context for each PDN connection may include at least a PDN connection ID, an APN, an operation mode, a network policy, a charging rule, a PCC rule, and a QoS rule.

  Furthermore, the default bearer and / or default access may be included in the UE context for each PDN connection.

  The APN is a label indicating the access destination of the network in accordance with the DNS naming rule.

  When the PDN connection is the first PDN connection, the operation mode is mode identification information indicating whether the UE_A 10 or the network can initiate data transmission / reception or start communication control.

  More specifically, for example, the Operation mode that can start communication control from the UE_A 10 may be a UE initiated mode.

  Further, the operation mode that can start communication control from the network and / or PGW_A 30 and / or PCRF_A 60 may be a network initiated mode.

  The Network Policy is a communication control policy on the network side, and may include a Network allowed mode. Or PCRF_A60 may memorize | store Network allowed mode separately from Network Policy.

  Charging Rule is a rule regarding charging. PCEF charges based on the Charging Rule determined by PCRF_A60.

  PCC Rule is a rule related to control of Network Policy and Charging Rule. Based on the PCC Rule, the PCEF performs communication control and charging.

  QoS Rule is a rule related to the QoS of a flow. The QoS Rule may be associated with the PCC Rule.

  Default Bearer is bearer identification information for identifying a default bearer in this PDN connection.

  If the PDN connection is a multi-access PDN connection, a plurality of default bearers may be established for the PDN connection. Therefore, a plurality of default bearers may be associated and managed for the multi-access PDN connection. Specifically, bearer identification information corresponding to each default bearer may be associated with the multi-access PDN connection and managed.

  Further, the PCRF_A 60 may manage the default bearer and the access network in association with each other.

  Specifically, PCRF_A 60 may store bearer identification information that identifies a default bearer for access network A and a default bearer for access network B. Here, the default bearer for the access network may be a default bearer for the access system of the access network. Therefore, the PCRF_A 60 may store a default bearer for 3GPP access and a default bearer for WLAN access in association with the multi-access PDN connection.

  The default bearer for the multi-access PDN may be an established default bearer. In other words, when only one default bearer is established for the multi-access PDN connection, the PCRF_A 60 stores one default bearer for the multi-access PDN connection and two default bearers for the multi-access PDN connection. In the state where the bearer is established, the PCRF_A 60 may store two default bearers for the multi-access PDN connection.

  When the PDN connection is a multi-access PDN connection, the PCRF_A 60 may store the default bearer as a UE context for each default bearer.

  Next, the default access may be information indicating 3GPP access or WLAN access. Here, 3GPP access may be an access system that is not WLAN access. More specifically, it may be information indicating an access network including E-UTRAN access, UTRAN access, and GERAN access.

  Alternatively, the 3GPP access may be more detailed information. For example, the 3GPP access may be an E-UTRAN access, a UTRAN access, or a GERAN access.

  When a plurality of default bearers are established, a default bearer may be selected based on default access, and user data may be transmitted / received using the selected default bearer. As described above, the default access is information associated with the access system and / or the access network, and may be information for selecting a bearer for data transmission / reception.

  The PCRF_A 60 is used when the PDN connection is a multi-access PDN connection, or when the UE_A 10 is simultaneously connected to a plurality of access systems and establishes a communication path for the PDN connection via a plurality of access networks. The PCRF_A 60 may store default access to the PDN connection.

  FIG. 12C shows an example of network capability stored in the PCRF_A 60. In Network capability, the NBIOM capability for each network, that is, for each PGW is stored.

  Here, NBIOM capability is identification information indicating whether or not the ability to establish the first PDN connection is supported for each network. In other words, the identification information indicates whether or not the PGW_A 30 supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  The NBIOM function may be information indicating that it has a function that enables establishment of a multi-access PDN connection.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the NBIOM capability may be identification information indicating a gateway that supports the NBIOM function. That is, it may mean that the PGW_A 30 is a gateway having a function of establishing the first PDN connection by the presence of NBIOM capability in the storage unit. In other words, the presence of the NBIOM capability in the storage unit may mean that the PGW_A 30 is a gateway that supports the NBIOM function.

  As illustrated in FIG. 12C, the PCRF_A 60 stores NBIOM capability in association with the PGW ID. Further, NBIOM capability may be stored in association with a plurality of PGWs.

  The PGW ID may be information for identifying the PGW_A 30, and may be, for example, an APN.

  FIG. 12 (d) shows an example of TWAG capability stored in PCRF_A60. In TWAG capability, identification information (NBIOM Capability) indicating whether or not the ability to establish the first PDN connection is supported for each TWAG is stored. In other words, the identification information indicates whether or not TWAG_A 74 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. That is, it may mean that the TWAG_A 74 is a gateway having a function of establishing the first PDN connection by the presence of NBIOM capability in the storage unit. In other words, the presence of the NBIOM capability in the storage unit may mean that the TWAG_A 74 is a gateway that supports the NBIOM function.

  As shown in the figure, NBIOM capability may be stored in association with TWAG ID, which is identification information of TWAG. When not associated with a TWAG ID, NBIOM Capability may mean the ability of the TWAG to store.

  When the TWAG ID and NBIOM capability are stored in association with each other, the PCRF_A 60 may store the TWAG capabilities of a plurality of TWAGs.

  In the case of a multi-access PDN connection, the PCRF_A 60 may store the TWAG capability and the network capability in the UE context, or store the TWAG capability and the network capability independently from the UE context.

  FIG.12 (e) is UE context for every Default Bearer. The UE context for each Default Bearer includes bearer identification information and Access network identification information. In addition, when there are a plurality of default bearers associated with the multi-access PDN connection, there may be a plurality of UE contexts for each default bearer.

  Bearer information is information for identifying a bearer. The bearer identification information may be an EPS bearer ID, for example.

  The access network information is information for identifying the access network. The access network information may be information indicating 3GPP access or WLAN access.

  FIG. 12F shows a UE context for each Dedicated Bearer. The UE context for each Dedicated Bearer includes transfer path identification information and Routing Rule. In addition, when there are a plurality of bearers associated with the multi-access PDN connection, a plurality of UE contexts for each Dedicated Bearer may exist.

  The Routing Rule may be information including the Routing Filter and / or the Routing Access Information and / or the Routing Rule Priority and / or the Routing Rule identifier. An example of the Routing Rule is shown in FIG.

  Here, the Routing Rule identifier may be information for identifying the Routing Rule associated with the PDN connection. The Routing Rule identifier may be the same information as the bearer identification information.

  The Routing Filter may be information including an IP header and / or an application ID and / or a TFT. The IP flow may be switched by including an IP header in the Routing Filter. Alternatively, the flow may be switched for each application by including the application ID in the Routing Filter. Alternatively, the IP flow may be switched based on the TFT by including the TFT in the Routing Filter.

  The Routing Access Information may be information indicating an access network through which the IP flow passes. For example, 3GPP or WLAN may be included in Routing Access Information. The Routing Access Information may be a Routing access type.

  The Routing Rule Priority may be information indicating the priority of the Routing Rule.

  In addition, the Routing Rule may include a Routing address. The routing address may be information indicating an IP address that can be routed. For example, the IP address of SGW_A35 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, the IP address of TWAG_A 74 may be used. Alternatively, it may be an IP address of MAG (Mobile Access Gateway).

  The Routing Rule may be notified from the UE_A 10 or the PGW_A 30. Or the value which PCRF_A60 memorize | stored as a default value beforehand may be sufficient.

  Also, a plurality of rules (rules) may be stored in the Routing Rule. Further, the routing rule may include a priority order in each rule.

[1.2.6. ePDG configuration]
FIG. 13 shows a device configuration of ePDG_A65. As shown in the figure, ePDG_A65 includes a network connection unit_A1320, a control unit_A1300, and a storage unit_A1340. The network connection unit_A 1320 and the storage unit_A 1340 are connected to the control unit_A 1300 via a bus.

  The control unit_A1300 is a functional unit for controlling the ePDG_A65. The control unit _A 1300 implements various processes by reading and executing various programs stored in the storage unit _A 1340.

  The network connection unit_A 1320 is a data transmission / reception unit that transmits / receives user data and / or control messages, and the ePDG_A 65 is a functional unit for connecting to the PGW_A 30. The network connection unit_A 1320 may include a transmission unit and a reception unit.

  The storage unit_A1340 is a functional unit that stores programs, data, and the like necessary for each operation of the ePDG_A65. The storage unit_A 1340 is configured by, for example, a semiconductor memory, an HDD (Hard Disk Drive), or the like.

  As illustrated in FIG. 13, the storage unit _A 1340 stores ePDG Capability_A 1342, Network capability_A 1344, and EPS bearer context_A 1346. Hereinafter, the information element memorize | stored in memory | storage part_A1340 is demonstrated.

  FIG. 14 shows information elements stored in the storage unit_A1340. FIG. 14A shows an example of ePDG Capability_A 1342 stored in ePDG_A 65. The ePDG Capability_A 1342 may store identification information (NBIFOM Capability) indicating whether the ability to establish the first PDN connection is supported for each ePDG. In other words, the ePDG Capability_A 1342 may be identification information indicating whether or not the ePDG_A 65 supports the NBIOM function.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A65 is a gateway having a function of establishing a first PDN connection. In other words, the existence of NBIOM capability in the storage unit_A 1340 may mean that the ePDG_A 65 is a gateway that supports the NBIOM function. Specifically, NBIOM Capability may include “allowed” or “Not allowed”.

  As shown in FIG. 14 (a), NBIOM capability may be stored in association with the identification information ePDG ID of ePDG_A65. When not associated with an ePDG ID, NBIOM Capability may mean the ability of the ePDG_A 65 to store.

  When the ePDG ID and NBIOM capability are stored in association with each other, the ePDG_A 65 may store ePDG capabilities of a plurality of ePDGs.

  In this case, when the UE_A 10 performs handover to another ePDG, the ePDG_A 65 may select a handover destination ePDG based on the ePDG capability_A 1342.

  Next, Network capability_A1344 will be described. FIG. 14B shows an example of Network capability_A 1344 stored in the ePDG_A 65. Network capability_A 1344 stores NBIOM capability for each network, that is, for each PGW.

  Here, NBIOM capability is identification information indicating whether or not the ability to establish the first PDN connection is supported for each network. In other words, the identification information indicates whether or not the PGW_A 30 supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in NBIOM Capability.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the NBIOM capability may be identification information indicating a gateway that supports the NBIOM function. That is, it may mean that the PGW_A 30 is a gateway having a function of establishing the first PDN connection by the presence of the NBIOM capability in the storage unit_A 1300. In other words, the presence of the NBIOM capability in the storage unit_A 1300 may mean that the PGW_A 30 is a gateway that supports the NBIOM function.

  As illustrated in FIG. 14B, the ePDG_A 65 may store NBIOM capability in association with the PGW ID. Further, as shown in the figure, each NGIFOM capability may be stored in association with a plurality of PGWs.

  The PGW ID may be information for identifying the PGW, and may be, for example, an APN (Access Point Name).

  Next, EPS bearer context_A 1346 will be described. The EPS bearer context_A 1346 may be classified into an EPS bearer context for each UE stored for each UE, an EPS bearer context for each PDN connection and a bearer, and / or an EPS bearer context for each transfer path.

  FIG.14 (c) shows the information element contained in the EPS bearer context for every UE. As can be seen from the figure, ePDG_A 65 stores UE NBIOM capability and NBIOM allowed for each UE.

  The UE NIFOM capability is the NBIOM capability of the UE. The UE NIFOM capability is identification information indicating whether or not the capability of establishing a first PDN connection is supported for each UE. In other words, the UE NBIOM capability is identification information indicating whether or not the UE supports the NBIOM function. More specifically, for example, “allowed” or “Not allowed” may be included in the UE NIFOM Capability.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Or UE NIFOM capability may be the identification information which shows that UE has the capability to establish a 1st PDN connection. That is, it may mean that the UE has a function of establishing the first PDN connection by the presence of UE NBIOM capability.

  In other words, the identification information may indicate that the UE supports the NBIOM function. That is, it may mean that the UE supports the NBIOM function by the presence of UE NBIOM capability in the storage unit.

  NBIOM allowed is identification information indicating an APN that is permitted to establish a PDN connection using the NBIOM. NBIOM may be associated with at least APN. NBIOM allowed may be associated with a plurality of APNs.

  In this embodiment, APN1 is associated with NBIOM allowed. That is, APN1 is allowed to establish a multi-access PDN connection. In other words, in this embodiment, UE_A 10 is permitted to establish a multi-access PDN connection using APN1. Note that APN1 is allowed to establish a conventional PDN connection instead of a multi-access PDN connection.

  Further, in the present embodiment, APN2 is not associated with NBIOM allowed. That is, in this embodiment, the APN 2 is not permitted to establish a multi-access PDN connection. That is, in this embodiment, UE_A10 cannot establish a multi-access PDN connection using APN2.

  NBIOM allowed may be stored before the PDN connection is established.

  The ePDG_A 65 may access the HSS_A 50 and acquire NBIFO allowed before the PDN connection is established and / or during the establishment procedure.

  Moreover, the identification information of UE may be contained in the EPS bearer context for every UE. The identification information of the UE may be IMSI.

  FIG. 14D shows an EPS bearer context for each PDN connection. The EPS bearer context for each PDN connection includes a PDN connection ID, a network allowed mode, an operation mode, a user plane connection ID, an ePDG MAC address, and an NBIOM permission (included).

  The PDN connection ID is identification information for identifying a PDN connection. In the present embodiment, UE_A10, ePDG_A65, and PGW_A30 may store the same PDN connection ID.

  The operation mode is a mode indicating whether the UE or the network can initiate data transmission or communication control when the PDN connection identified by the PDN connection ID is the first PDN connection. Identification information.

  More specifically, for example, the operation mode in which communication control can be started from the UE may be a UE initiated mode.

  Further, the operation mode that can start communication control from the network and / or the PGW_A 30 and / or the PCRF_A 60 may be a network initiated mode.

  Network allowed mode indicates an operation mode permitted by the network. The network allowed mode may include a UE initiated mode, a network initiated mode, or both.

  User plane connection ID is identification information for identifying a connection used for transmission of user data when a UE establishes a communication path via ePDG_A65.

  ePDG MAC address is the physical address of ePDG.

  The NBIOM permission is information indicating that the PDN connection established by the PDN connection ID has established a multi-access PDN connection. In other words, NBIOM permission indicates that the first PDN connection has been established.

  That is, the ePDG_A 65 stores the NBIOM permission, which means that this PDN connection is the first PDN connection.

  NBIOM permission is identification information stored in the ePDG_A 65 by establishing a PDN connection.

  The ePDG_A 65 may access the HSS_A 50 and acquire the NBIOM permission while the PDN connection is established. Alternatively, the ePDG_A 65 may store the NBIOM permission based on the establishment of the multi-access PDN connection.

  Next, an EPS bearer context for each bearer and / or transfer path will be described. As shown in FIG. 14E, the EPS bearer context for each bearer and / or transfer path may include transfer path identification information and Routing Rule.

  The transfer path identification information is information for identifying a transfer path and / or a bearer. The transfer path identification information may be an EPS bearer ID, for example.

  Routing Rule indicates a correspondence between the Routing Filter and the Routing address or Routing access type. Based on this association, it is determined whether to use a communication path via a 3GPP access network or a communication path via a WLAN access network.

  Here, Routing access type indicates an access network through which the flow passes. For example, this indicates 3GPP or WLAN.

  Also, Routing address indicates an IP address that can be routed. For example, the IP address of SGW_A35 may be used. Alternatively, the IP address of ePDG_A65 may be used. Alternatively, it may be an IP address of MAG (Mobile Access Gateway).

  The Routing Rule may be notified from the PGW or PCRF_A 60 or may be notified from the UE_A 10. Alternatively, the value stored in advance as a default value by ePDG_A65 may be used.

  The IP flow may be switched by including an IP header in the Routing Filter. Alternatively, the flow may be switched for each application by including the application ID in the Routing Filter. Alternatively, a TFT may be included.

  A plurality of rules may be stored in the Routing Rule. Further, the routing rule may include a priority order in each rule.

  The ePDG capability and the network capability may be included in the EPS bearer context_A 1346.

[1.3. Explanation of the initial state]
The initial state in this embodiment will be described. An example of the initial state in this embodiment is shown in FIG.

  In the initial state in the present embodiment, the UE_A 10 is in a state where a multi-access PDN connection is established with the core network_A 90 via the access network A and the access network B. Specifically, the UE_A 10 establishes a multi-access PDN connection that establishes a communication path by 3GPP access and a communication path by WLAN with the PGW_A 30 included in the core network_A 90. Here, 3GPP access may be an access system that is not WLAN access. More specifically, it may be information indicating an access network including E-UTRAN access, UTRAN access, and GERAN access.

  The communication path by 3GPP access is a communication path established between the UE_A 10 and the PGW_A 30 included in the core network_A 90 via the LTE base station eNB_A 45 included in the access network A and the SGW_A 35 included in the core network_A 90. It's okay. In other words, the communication path by 3GPP access is a communication path configured by a transfer path between UE_A10 and eNB_A45, a transfer path between eNB_A45 and SGW_A35, and a transfer path between SGW_A35 and PGW_A30. Also good. Moreover, the communication path by 3GPP access may be comprised by the bearer.

  The UE_A 10 and the PGW_A 30 may establish a plurality of 3GPP access communication paths associated with the multi-access PDN connection. Note that the UE_A 10 and the PGW_A 30 may use the first established transfer path as a default bearer among a plurality of 3GPP access communication paths associated with the multi-access PDN connection. Note that UE_A 10 and PGW_A 30 may store a default bearer in association with information for identifying 3GPP access.

  A communication path by WLAN access may be a communication path established between UE_A 10 and PGW_A 30 included in core network_A 90 via TWAG_A 74 included in access network B. In other words, the communication path by WLAN access may be a communication path configured by a transfer path between UE_A 10 and TWAG_A 74 and a transfer path between TWAG_A 74 and PGW_A 30. Moreover, the communication path by WLAN access may be comprised by the bearer. Moreover, the communication path by WLAN access may be comprised by transfer paths other than a bearer. In that case, the information for identifying the bearer may be information for identifying a transfer path other than the bearer.

  The UE_A 10 and the PGW_A 30 may establish communication paths using a plurality of WLAN accesses associated with the multi-access PDN connection. Note that the UE_A 10 and the PGW_A 30 may use the first established transfer path as a default bearer among a plurality of WLAN access communication paths associated with the multi-access PDN connection. Note that UE_A 10 and PGW_A 30 may store a default bearer in association with information for identifying WLAN access.

  UE_A10 and PGW_A30 may memorize | store the context for each communication path matched with the multi-access PDN connection. The context for each communication path associated with the multi-access PDN connection may include a communication path context by 3GPP access and a communication path context by WLAN access.

  The context for the communication path by 3GPP access includes the default bearer associated with the communication path by 3GPP access in FIGS. 8 and 10, the UE context and the EPS bearer context for each default bearer associated with the communication path by 3GPP access. And a UE context and an EPS bearer context for each Dedicated Bearer associated with a communication path by 3GPP access.

  The context for the communication path by the WLAN access includes the Default Bearer associated with the communication path by the WLAN access in FIGS. 8 and 10, the UE context and the EPS bearer context for each Default Bearer associated with the communication path by the WLAN access. And a UE context and an EPS bearer context for each Dedicated Bearer associated with a communication path by WLAN access.

  UE_A10 and PGW_A30 may transmit and receive user data based on the context for each communication path associated with the stored multi-access PDN connection. Further, when there are a plurality of default bearers associated with the multi-access PDN connection, the UE_A 10 and the PGW_A 30 are based on the default access associated with the context for each communication path associated with the multi-access PDN connection. A default bearer to be used may be selected.

  Next, first to third examples will be described as specific examples of a method of transmitting and receiving user data by the UE_A 10 and the PGW_A 30 in the initial state.

  First, a first example will be described. FIG. 15 illustrates an example of the UE context of the UE_A 10 and / or the EPS bearer context of the PGW_A 30 in the first example.

  The UE_A 10 and the PGW_A 30 first compare the corresponding Routing Filter with the user data in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare user data to be transmitted with the Routing Filter in the order of Filter A 1, Filter B 1, Filter A 2, and Filter B 2.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A10 and PGW_A30 may transmit user data using Dedicated Bearer A2 corresponding to Filter A2.

  If the user data does not match any Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit the user data using the default bearer corresponding to the access network identified by the default access (Default Access). For example, if the user data to be transmitted does not match Filter A1, Filter B1, Filter A2, and Filter B2, UE_A10 and PGW_A30 use the default bearer 1 that is the default bearer of the 3GPP access network identified by the default access. May be sent.

  Next, a second example will be described. FIG. 16 shows an example of the UE context of UE_A 10 and / or the EPS bearer context of PGW_A 30 in the second example.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare user data to be transmitted with Routing Filter in the order of Filter A 1, Filter B 1, Filter A 2, Filter B 2, ANY 1, ANY 2. Here, ANY 1 and / or ANY 2 may be a filter describing a rule that matches all user data.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches ANY 1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to ANY 1.

  Next, a third example will be described. FIG. 17 illustrates an example of the UE context of the UE_A 10 and / or the EPS bearer context of the PGW_A 30 in the third example.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare user data to be transmitted with Routing Filter in the order of Filter A 1, Filter B 1, Filter A 2, Filter B 2, Filter D 1, and Filter D 2. Here, Filter D1 and / or Filter D2 may be a filter in which rules that match all user data corresponding to a specific UE_A10 and / or PGW_A30 are described. For example, Filter D1 may be a filter in which a rule that matches the source IP address of UE_A10 and / or PGW_A30 is described.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches Filter D1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to Filter D1.

  Although the initial state has been described above, the initial state is not limited to this, and another PDN connection may be established as long as the UE_A 10 has established a multi-access PDN connection.

[1.4. Explanation of PDN connection disconnection procedure]
[1.4.1. Explanation of UE-led PDN connection disconnection procedure (WLAN access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by WLAN access associated with a multi-access PDN connection led by UE will be described with reference to FIG.

  Note that the UE_A 10 may detect the deterioration of the radio wave state of the WLAN access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, UE_A10 may start a PDN connection disconnection procedure at arbitrary timings.

  First, the UE_A 10 transmits a PDN disconnect request to the TWAG_A 74 (S1802). The UE_A 10 may transmit a PDN connection disconnection request message including at least a PDN disconnection request message ID (PDN disconnect request message identity), a procedure transaction ID (Procedure transaction identity), and a PDN connection ID (PDN connection ID). Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the PDN connection disconnection request. Further, the UE_A 10 may include Cause and / or PCO (Protocol Configuration Options) in the PDN connection disconnection request. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the second identification information, it may be requested to disconnect only the communication path by the WLAN access associated with the multi-access PDN connection. In other words, the first identification information and / or the second identification information may be information indicating that it is requested to disconnect only the communication path by the WLAN access associated with the multi-access PDN connection.

  The procedure transaction ID may be information for identifying a PDN connection disconnection procedure.

  The PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  The Cause may be information indicating the reason for transmitting the PDN connection disconnection request.

  The PCO may be protocol information associated with the PDN connection. Further, the UE_A 10 may include request identification information in the PCO. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  The TWAG_A 74 receives the PDN connection disconnection request transmitted by the UE_A 10. The TWAG_A 74 receives the PDN connection disconnection request and / or transmits a session deletion request to the PGW_A 30 based on the first identification information and / or the second identification information included in the PDN connection disconnection request (S1804). The session deletion request may be a message for requesting deletion of the transfer path.

  The TWAG_A 74 deletes at least the first identification information and / or the second identification information based on the reception of the PDN connection disconnection request and / or the first identification information and / or the second identification information included in the PDN connection disconnection request. It may be sent in the request. Further, the TWAG_A 74 may include the PDN connection ID in the session deletion request.

  Note that TWAG_A 74 does not include the first identification information and / or the second identification information when the identification information of the first identification information and / or the second identification information is not included in the PDN connection disconnection request. A session deletion request may be sent.

  The PGW_A 30 receives the session deletion request transmitted by the TWAG_A 74. The PGW_A 30 may execute an IP-CAN session update procedure with the PCRF_A 60 based on the reception of the session deletion request and / or the first identification information and / or the second identification information included in the session deletion request. (S1806).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. It may be executed as part of the update procedure.

  Note that the PGW_A 30 may execute the IP-CAN session update procedure in order to notify the PCRF_A 60 that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 includes information indicating whether the communication path to be deleted is a communication path associated with a multi-access PDN connection or a communication path associated with a single access PDN connection, and / or first identification information and / or The identification information 2 may be included in a control message in the IP-CAN session procedure and transmitted to the PCRF_A 60.

  More specifically, when the communication path to be deleted is a communication path associated with the multi-access PDN connection, the PGW_A 30 includes information indicating the WLAN access network, the PDN connection ID, and the PDN connection is the multi-access PDN. Information indicating the connection and the first identification information and / or the second identification information are transmitted to the PCRF_A 60. Alternatively, when the communication path to be deleted is a communication path associated with the single access PDN connection, the PGW_A 30 is information indicating the WLAN access network, the PDN connection ID, and the PDN connection is a single access PDN connection. Is sent to PCRF_A60.

  Further, the PCRF_A 60 receives at least the first identification information and / or the third identification information in the control message in the IP-CAN session update procedure with the PGW_A 30 based on the reception of the first identification information and / or the second identification information. You may transmit to PGW_A30 including identification information.

  The PCRF_A 60 may execute an IP-CAN session update procedure in order to notify the PGW_A 30 of charging information and / or QoS control information and / or routing information.

  Here, the third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the session deletion request or completes the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the first identification information included in the IP-CAN session update procedure. Based on the identification information of 1 and / or the third identification information, a session deletion response is transmitted to TWAG_A 74 (S1808).

  The PGW_A 30 is included in the reception of the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, at least the first identification information and / or the third identification information may be included in the session deletion response and transmitted.

  Note that the method of acquiring the third identification information by the PGW_A 30 is not limited to the method of acquiring from the PCRF_A 60 in the IP-CAN session update procedure described so far, and may be another example. For example, the PGW_A 30 may not acquire from the PCRF_A 60 in the IP-CAN session update procedure, and the PGW_A 30 may generate the third identification information and transmit it by including it in the session deletion response.

  The PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits a session deletion response and / or first identification information and / or second identification information included in the session deletion request and / or Communication by WLAN access associated with the multi-access PDN connection identified by the PDN connection ID based on the PDN connection ID and / or the first identification information and / or the third identification information included in the IP-CAN session update procedure Only the road may be cut. More specifically, the PGW_A 30 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Therefore, the PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits the session deletion response and / or the first identification information and / or the second identification information included in the session deletion request. And / or the default access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the IP-CAN session update procedure. May be deleted. In this way, the PGW_A 30 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  The PGW_A 30 is associated with the multi-access PDN connection based on the detection that the connectivity of the WLAN access system is lost due to the deterioration of the radio wave condition of the WLAN access system or the instability of the connectivity. The context for the communication path by the WLAN access and / or the default access may be deleted.

  The TWAG_A 74 receives the session deletion response transmitted by the PGW_A 30. The TWAG_A 74 transmits a PDN disconnect accept to the UE_A 10 based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response (S1810). Note that the PDN connection disconnection acceptance message may be a control message indicating that the disconnection of the PDN connection is permitted, and may be an EPS bearer context deactivation request (Deactivate EPS Bearer context request). The PDN connection disconnection acceptance message may be a response message to the PDN connection disconnection request.

  The TWAG_A 74 receives at least the PDN disconnection accept message identity and the procedure transaction ID based on the first identification information and / or the third identification information included in the reception of the session deletion response and / or the session deletion response. And the PDN connection ID may be included in the PDN connection disconnection acceptance and transmitted. Further, the TWAG_A 74 may include at least the first identification information and / or the third identification information in the PDN connection disconnection acceptance. Further, the TWAG_A 74 may include the PCO in the PDN connection disconnection acceptance. Note that the TWAG_A 74 may transmit the first identification information and / or the third identification information included in the PCO.

  Here, the PDN connection disconnection acceptance message ID may be a message type representing a PDN connection disconnection acceptance message.

  UE_A10 receives the PDN connection disconnection acceptance transmitted by TWAG_A74.

  The UE_A 10 receives the PDN connection disconnection acceptance and / or the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the PDN connection disconnection acceptance and / or the PDN connection ID. Only the communication path by the WLAN access associated with can be disconnected. More specifically, the UE_A 10 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, UE_A10 may delete the default access matched with the multi-access PDN connection, when all the contexts for the communication path by the WLAN access matched with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, the UE_A 10 receives the PDN connection disconnection acceptance and / or the multi-access identified by the PDN connection ID based on the first identification information and / or the third identification information and / or the PDN connection ID included in the PDN connection disconnection acceptance. The default access associated with the PDN connection may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  The UE_A 10 is associated with the multi-access PDN connection based on the detection that the connectivity of the WLAN access system has been lost due to the deterioration of the radio wave condition of the WLAN access system or the instability of the connectivity. The context for the communication path by the WLAN access and / or the default access may be deleted.

  Upon completion of the UE-initiated PDN connection disconnection procedure (WLAN access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for WLAN access. The multi-access PDN connection that does not have a communication path by WLAN access may be a multi-access PDN connection that has only a communication path by 3GPP access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when having a multi-access PDN connection having only a communication path by 3GPP access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After the UE-initiated PDN connection disconnection procedure (WLAN access network) is completed, the UE_A 10 and the PGW_A 30 may transmit and receive user data based on the stored context for the communication path using 3GPP access.

  Next, first to third examples will be described as specific examples of a method in which UE_A 10 and PGW_A 30 transmit and receive user data after completion of the UE-led PDN connection disconnection procedure (WLAN access network).

  First, a first example will be described. Note that the context for the communication path by the 3GPP access of the UE_A 10 and the PGW_A 30 in the first example may be the context for each bearer shown in FIG. 15 from which the context for the communication path by the WLAN access is deleted. Good.

  The UE_A 10 and the PGW_A 30 first compare the corresponding Routing Filter with the user data in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare the user data to be transmitted with the Routing Filter in the order of Filter A 1 and Filter A 2.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A10 and PGW_A30 may transmit user data using Dedicated Bearer A2 corresponding to Filter A2.

  If the user data does not match any Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit the user data using the default bearer. For example, when user data to be transmitted does not match Filter A1 and Filter A2, UE_A10 and PGW_A30 may transmit user data using Default Bearer 1 which is a default bearer of the 3GPP access network.

  Next, a second example will be described. Note that the context for the communication path by 3GPP access of UE_A10 and PGW_A30 in the second example may be the context for each bearer shown in FIG. 16 from which the context for the communication path by WLAN access is deleted. Good.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare the user data to be transmitted with the Routing Filter in the order of Filter A 1, Filter A 2, ANY 1. Here, ANY 1 may be a filter describing a rule that matches all user data.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches ANY 1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to ANY 1.

  Next, a third example will be described. Note that the context for the communication path by the 3GPP access of the UE_A 10 and the PGW_A 30 in the third example may be obtained by deleting the context for the communication path by the WLAN access from the context for each bearer illustrated in FIG.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A10 and PGW_A30 compare the user data to be transmitted with the Routing Filter in the order of Filter A1, Filter A2, and Filter D1. Here, Filter D1 may be a filter in which a rule that matches all user data corresponding to a specific UE_A10 and / or PGW_A30 is described. For example, Filter D1 may be a filter in which a rule that matches the source IP address of UE_A10 and / or PGW_A30 is described.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches Filter D1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to Filter D1.

  In the example of the UE-initiated PDN connection disconnection procedure (WLAN access network), the case has been described where only the communication path by WLAN access associated with the multi-access PDN connection is disconnected.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[1.4.2. Explanation of network-led PDN connection disconnection procedure (WLAN access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by WLAN access associated with a multi-access PDN connection led by a network will be described with reference to FIG.

  The PCRF_A 60 and the PGW_A 30 may detect the deterioration of the radio wave state of the WLAN access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, PCRF_A60 and PGW_A30 may start the PDN connection disconnection procedure at an arbitrary timing.

  First, the PCRF_A 60 transmits a message for requesting an IP-CAN update procedure to the PGW_A 30 in order to start the PDN connection disconnection procedure (S1902). The message for requesting the IP-CAN update procedure may include at least first identification information and / or third identification information.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the message for requesting the IP-CAN update procedure transmitted by the PCRF_A 60. The PGW_A 30 receives the message for requesting the IP-CAN update procedure and / or the TWAG_A 74 based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. A session deletion request is transmitted to (S1904).

  The PGW_A 30 receives at least the message for requesting the IP-CAN update procedure and / or at least based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. The first identification information and / or the third identification information may be included in the session deletion request and transmitted.

  Note that the method of starting the PDN connection disconnection procedure is not limited to the method of starting PCRF_A 60 in the IP-CAN session update procedure described so far, and PGW_A 30 may start. At this time, the PGW_A 30 may generate the first identification information and / or the third identification information, and transmit it by including it in the session deletion request.

  The TWAG_A 74 receives the session deletion request transmitted by the PGW_A 30. The TWAG_A 74 transmits a PDN disconnect request to the UE_A 10 based on the reception of the session deletion request and / or the first identification information and / or the third identification information included in the session deletion request (S1906). The PDN connection disconnection request may be a message for requesting disconnection of the PDN connection.

  The TWAG_A 74 receives at least a PDN disconnect request message ID and a procedure transaction ID based on the first identification information and / or the third identification information included in the reception of the session deletion request and / or the session deletion request. A PDN connection disconnection request may be transmitted including (Procedure transaction identity) and a PDN connection ID (PDN connection ID). Further, the TWAG_A 74 may include at least the first identification information and / or the third identification information in the PDN connection disconnection request. Further, the UE_A 10 may include Cause and / or PCO (Protocol Configuration Options) in the PDN connection disconnection request.

  Here, the PDN connection disconnection request message ID may be a message type representing a PDN connection disconnection request message.

  The procedure transaction ID may be information for identifying a PDN connection disconnection procedure.

  The PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  The Cause may be information indicating the reason for transmitting the PDN connection disconnection request.

  The PCO may be protocol information associated with the PDN connection. Further, the TWAG_A 74 may include request identification information in the PCO. Note that the TWAG_A 74 may transmit the first identification information and / or the third identification information included in the PCO.

  UE_A10 receives the PDN connection disconnection request transmitted by TWAG_A74. The UE_A 10 transmits a PDN disconnect accept to the TWAG_A 74 based on the reception of the PDN connection disconnection request and / or the first identification information and / or the third identification information included in the PDN connection disconnection request ( S1908). The PDN connection disconnection acceptance message may be a control message indicating that disconnection of the PDN connection is permitted. The PDN connection disconnection acceptance message may be a response message to the PDN connection disconnection request.

  The UE_A 10 receives the PDN connection disconnection request and / or based on the first identification information and / or the third identification information included in the PDN connection disconnection request, at least a PDN disconnection accept message identity (PDN disconnection accept message identity) and The procedure transaction ID and the PDN connection ID may be included in the PDN connection disconnection acceptance and transmitted. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the PDN connection disconnection acceptance. Furthermore, UE_A10 may include PCO in the PDN connection disconnection acceptance. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  Here, the second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the second identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PDN connection disconnection acceptance message ID may be a message type representing a PDN connection disconnection acceptance message.

  The UE_A 10 receives the PDN connection disconnection request and / or the transmission of the PDN connection disconnection request and / or the PDN connection based on the first identification information and / or the third identification information and / or the PDN connection ID included in the PDN connection disconnection request. Only the communication path by the WLAN access associated with the multi-access PDN connection identified by the connection ID may be disconnected. More specifically, the UE_A 10 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, UE_A10 may delete the default access matched with the multi-access PDN connection, when all the contexts for the communication path by the WLAN access matched with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, the UE_A 10 is based on the reception of the PDN connection disconnection request and / or the transmission of the first identification information and / or the third identification information and / or the PDN connection ID and / or the PDN connection disconnection acceptance included in the PDN connection disconnection request. The default access associated with the multi-access PDN connection identified by the PDN connection ID may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  The TWAG_A 74 receives the PDN connection disconnection acceptance transmitted by the UE_A 10. The TWAG_A 74 transmits a session deletion response to the PGW_A 30 based on the reception of the PDN connection disconnection acceptance and / or the first identification information and / or the second identification information included in the PDN connection disconnection acceptance (S1910). Note that it may be a response message to the session deletion request.

  The TWAG_A 74 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the PDN connection acceptance and / or the PDN connection disconnection acceptance. May be included in the transmission. Further, TWAG_A 74 may include the PDN connection ID in the session deletion response.

  The PGW_A 30 receives the session deletion response transmitted by the TWAG_A 74. The PGW_A 30 transmits a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. (S1912).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. It may be transmitted by being included in a message for notifying completion of the procedure.

  When the PGW_A 30 starts the PDN connection disconnection procedure instead of the PCRF_A 60, the PGW_A 30 may not transmit a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure.

  The PGW_A 30 receives a session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or first identification information and / or second identification information and / or PDN connection included in the session deletion response Based on the ID, only the communication path by the WLAN access associated with the multi-access PDN connection identified by the PDN connection ID may be disconnected. More specifically, the PGW_A 30 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Accordingly, the PGW_A 30 receives the session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or the first identification information and / or the second identification information included in the session deletion response and / or Based on the PDN connection ID, the default access associated with the multi-access PDN connection identified by the PDN connection ID may be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  Upon completion of the network-driven PDN connection disconnection procedure (WLAN access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for WLAN access. The multi-access PDN connection that does not have a communication path by WLAN access may be a multi-access PDN connection that has only a communication path by 3GPP access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when having a multi-access PDN connection having only a communication path by 3GPP access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After completing the network-initiated PDN connection disconnection procedure (WLAN access network), the UE_A 10 and the PGW_A 30 may transmit and receive user data based on the stored context for the communication path by 3GPP access.

  Note that the UE_A 10 and PGW_A 30 that transmit and receive user data after the completion of the network-initiated PDN connection disconnection procedure (WLAN access network) is the UE-initiated PDN connection disconnection procedure (WLAN access Network) It may be the same as the method of transmission / reception after completion. Therefore, the description of the user data transmission / reception method is omitted here.

  In the example of the network-initiated PDN connection disconnection procedure (WLAN access network), the case where only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected has been described.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[1.4.3. Explanation of UE-led PDN connection disconnection procedure (3GPP access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by a UE will be described with reference to FIG.

  Note that the UE_A 10 may detect the deterioration of the radio wave state of the 3GPP access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, UE_A10 may start a PDN connection disconnection procedure at arbitrary timings.

  UE_A10 first transmits a PDN disconnection request (PDN disconnect request) to MME_A40 via eNB_A45 (S2002). The UE_A 10 includes at least a protocol discriminator, an EPS bearer ID, a procedure transaction ID, a PDN disconnect request message ID, and a link. The PDN connection disconnection request may be transmitted including an EPS bearer ID and a spare half octet. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the PDN connection disconnection request. Further, the UE_A 10 may include PCO (Protocol Configuration Options) in the PDN connection disconnection request. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  Thus, by transmitting the first identification information and / or the second identification information, it may be requested to disconnect only the communication path by 3GPP access associated with the multi-access PDN connection. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is requested to be disconnected.

  The protocol discriminator may be information for identifying the type of protocol.

  The EPS bearer ID may be information for identifying a bearer.

  The procedure transaction ID may be information for identifying a PDN connection disconnection procedure.

  The PDN connection disconnection request message ID may be a message type representing a PDN connection disconnection request message.

  The link EPS bearer ID (Linked EPS bearer identity) may be information for identifying a default associated with a certain bearer. The link EPS bearer ID may be information for identifying a bearer associated with a packet filter.

  The spare half octet may be an element for filling a vacant bit.

  The PCO may be protocol information associated with the PDN connection. Further, the UE_A 10 may include request identification information in the PCO. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  The MME_A 40 receives the PDN connection disconnection request transmitted by the UE_A 10. The MME_A 40 receives the PDN connection disconnection request and / or transmits a session deletion request to the SGW_A 35 based on the first identification information and / or the second identification information included in the PDN connection disconnection request (S2004). The session deletion request may be a message for requesting deletion of the transfer path.

  The MME_A 40 deletes at least the first identification information and / or the second identification information based on the reception of the PDN connection disconnection request and / or the first identification information and / or the second identification information included in the PDN connection disconnection request. It may be sent in the request. Further, the MME_A 40 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  Note that the MME_A 40 does not include the first identification information and / or the second identification information when the identification information of the first identification information and / or the second identification information is not included in the PDN connection disconnection request. A session deletion request may be sent.

  Here, the PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  The SGW_A 35 receives the session deletion request transmitted by the MME_A 40. The SGW_A 35 receives the session deletion request and / or transmits a session deletion request to the PGW_A 30 based on the first identification information and / or the second identification information included in the session deletion request (S2006).

  The SGW_A 35 receives at least the first identification information and / or the second identification information in the session deletion request based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. You may include and transmit. Further, the SGW_A 35 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  Note that the SGW_A 35 does not include the first identification information and / or the second identification information when the session deletion request does not include the first identification information and / or the second identification information. A delete request may be sent.

  The PGW_A 30 receives the session deletion request transmitted by the SGW_A 35. The PGW_A 30 may execute an IP-CAN session update procedure with the PCRF_A 60 based on the reception of the session deletion request and / or the first identification information and / or the second identification information included in the session deletion request. (S2008).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. It may be executed as part of the update procedure.

  Note that the PGW_A 30 may execute the IP-CAN session update procedure to notify the PCRF_A 60 that only the 3GPP access communication path associated with the multi-access PDN connection is to be disconnected.

  The PGW_A 30 includes information indicating whether the communication path to be deleted is a communication path associated with a multi-access PDN connection or a communication path associated with a single access PDN connection, and / or first identification information and / or The identification information 2 may be included in a control message in the IP-CAN session procedure and transmitted to the PCRF_A 60.

  More specifically, when the communication channel to be deleted is a communication channel associated with the multi-access PDN connection, the PGW_A 30 indicates that information indicating the 3GPP access network and that the PDN connection is a multi-access PDN connection. The information to be shown and the first identification information and / or the second identification information are transmitted to the PCRF_A 60. Alternatively, when the communication path to be deleted is a communication path associated with the single access PDN connection, the PGW_A 30 includes information indicating the 3GPP access network and information indicating that the PDN connection is a single access PDN connection. It transmits to PCRF_A60.

  Further, the PCRF_A 60 receives at least the first identification information and / or the third identification information in the control message in the IP-CAN session update procedure with the PGW_A 30 based on the reception of the first identification information and / or the second identification information. You may transmit to PGW_A30 including identification information.

  The PCRF_A 60 may execute an IP-CAN session update procedure in order to notify the PGW_A 30 of charging information and / or QoS control information and / or routing information.

  Here, the third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the session deletion request or completes the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the first identification information included in the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, a session deletion response is transmitted to the SGW_A 35 (S2010).

  The PGW_A 30 is included in the reception of the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, at least the first identification information and / or the third identification information may be included in the session deletion response and transmitted.

  Note that the method of acquiring the third identification information by the PGW_A 30 is not limited to the method of acquiring from the PCRF_A 60 in the IP-CAN session update procedure described so far, and may be another example. For example, the PGW_A 30 may not acquire from the PCRF_A 60 in the IP-CAN session update procedure, and the PGW_A 30 may generate the third identification information and transmit it by including it in the session deletion response.

  The PGW_A 30 receives a session deletion request and / or completes an IP-CAN session update procedure and / or transmits a session deletion response and / or first identification information and / or second identification information and / or PDN connection included in the session deletion request Only the communication path by the 3GPP access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the ID and / or IP-CAN session update procedure May be cut. More specifically, the PGW_A 30 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Therefore, the PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits the session deletion response and / or the first identification information and / or the second identification information included in the session deletion request. And / or the default access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the IP-CAN session update procedure. May be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  The PGW_A 30 is associated with the multi-access PDN connection based on the detection that the connectivity of the 3GPP access system has been lost due to the deterioration of the radio wave condition of the 3GPP access system or the instability of the connectivity. Alternatively, the context for the communication path by 3GPP access and / or default access may be deleted. The SGW_A 35 receives the session deletion response transmitted by the PGW_A 30. The SGW_A 35 transmits the session deletion response to the MME_A 40 based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response (S2012).

  The PGW_A 30 receives at least the first identification information and / or the third identification information in the session deletion response based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. You may include and send it.

  The MME_A 40 receives the session deletion response transmitted by the SGW_A 35. The MME_A 40 receives the session deletion response and / or transmits an EPS bearer context deactivation request (Deactivate EPS Bearer context request) to the eNB_A 45 based on the first identification information and / or the third identification information included in the session deletion response. (S2014). Note that the EPS bearer context deactivation request message may be a control message indicating that disconnection of the PDN connection is permitted, and may be a PDN disconnection accept. Further, the EPS bearer context deactivation request message may be a response message to the PDN connection disconnection request.

  The MME_A 40 receives at least the protocol discriminator, the EPS bearer ID, the procedure transaction ID, and the EPS based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. A bearer context deactivation request message ID (Deactivate EPS Bearer context request message identity) and EMS Couse may be included in the EPS bearer context deactivation request and transmitted. Further, the MME_A 40 may include at least the first identification information and / or the third identification information in the EPS bearer context deactivation request. Further, the MME_A 40 may include the PCO and / or the T3396 value (T3396 value) and / or the WLAN Offload Indication in the EPS bearer context deactivation request. Note that the MME_A 40 may transmit the first identification information and / or the second identification information included in the PCO.

  Here, the EPS bearer context deactivation request message ID may be a message type representing an EPS bearer context deactivation request message.

  The EMS Cause may be information indicating the reason for transmitting the EPS bearer context deactivation request.

  The T3396 value may be the value of the T3396 timer included when the ESM Cause represents an insufficient resource.

  The WLAN offload information may be information indicating whether traffic can be offloaded to the WLAN access network in the current PDN connection.

  eNB_A45 receives the EPS bearer context deactivation request transmitted by MME_A40. The eNB_A 45 transfers the EPS bearer context deactivation request to the UE_A 10 based on the reception of the EPS bearer context deactivation request.

  eNB_A45 may transmit an RRC connection configuration request (RRC Connection Reconfiguration) at least to UE_A10 together with the EPS bearer context deactivation request (S2016).

  UE_A10 receives the RRC connection setting request transmitted by eNB_A45. Furthermore, UE_A10 receives the EPS bearer context deactivation request transmitted by MME_A40 and transferred by eNB_A45.

  UE_A10 transmits RRC connection setting completion (RRC Connection Reconfiguration Complete) to eNB_A45 based on reception of the RRC connection setting request (S2018).

  eNB_A45 receives the RRC connection setup completion transmitted by UE_A10. The eNB_A 45 transmits a Deactivate Bearer Response to the MME 40 based on the completion of RRC connection setting (S2020).

  The MME 40 receives the deactive bearer response transmitted by the eNB 45.

  The UE_A 10 receives the EPS bearer context deactivation request and / or the EPS bearer context deactivation to the MME_A 40 via the eNB_A 45 based on the first identification information and / or the third identification information included in the EPS bearer context deactivation request. An activation acceptance (Deactivate EPS Bearer context accept) is transmitted (S2022) (S2224).

  The UE_A 10 includes at least the protocol discriminator, the EPS bearer ID, the procedure transaction ID, and the EPS bearer context accept message identity (Activate default EPS bearer context accept message identity) in the EPS bearer context deactivation acceptance. You may send it.

  In addition, the PCO may be included in the EPS bearer context deactivation acceptance.

  Here, the EPS bearer context deactivation acceptance message ID may be a message type representing an EPS bearer context deactivation acceptance message.

  The UE_A 10 is identified by the EPS bearer ID based on the reception of the EPS bearer context deactivation request and / or the first identification information and / or the third identification information and / or the EPS bearer ID included in the EPS bearer context deactivation request. When the bearer to be used is a default bearer, only the communication path by the 3GPP access associated with the multi-access PDN connection associated with the default bearer identified by the EPS bearer ID may be disconnected. More specifically, the UE_A 10 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection. Note that, when the bearer identified by the received EPS bearer ID is not the default bearer, the UE_A 10 does not have to disconnect the communication path by the 3GPP access.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, the UE_A 10 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Accordingly, the UE_A 10 receives the EPS bearer context deactivation request and / or the EPS bearer ID based on the first identification information and / or the third identification information and / or the EPS bearer ID included in the EPS bearer context deactivation request. When the bearer identified by (1) is the default bearer, the default access associated with the multi-access PDN connection associated with the default bearer identified by the EPS bearer ID may be deleted. Note that when the bearer identified by the received EPS bearer ID is not the default bearer, the UE_A 10 does not have to delete the default access.

  In this way, the UE_A 10 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  Further, UE_A 10 is associated with a multi-access PDN connection based on the detection that the connectivity of the 3GPP access system is lost due to the deterioration of the radio wave condition of the 3GPP access system or the instability of the connectivity. Alternatively, the context for the communication path by 3GPP access and / or default access may be deleted.

  Upon completion of the UE-initiated PDN connection disconnection procedure (3GPP access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path by 3GPP access. The multi-access PDN connection that does not have a communication path by 3GPP access may be a multi-access PDN connection that has only a communication path by WLAN access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when there is a multi-access PDN connection having only a communication path by WLAN access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After the UE-initiated PDN connection disconnection procedure (3GPP access network) is completed, the UE_A 10 and the PGW_A 30 may transmit / receive user data based on the stored context for the communication path by the WLAN access.

  Next, first to third examples will be described as specific examples of a method in which UE_A 10 and PGW_A 30 transmit and receive user data after completion of a UE-led PDN connection disconnection procedure (3GPP access network).

  First, a first example will be described. Note that the context for the communication path by the WLAN access of the UE_A 10 and the PGW_A 30 in the first example may be one obtained by deleting the context for the communication path by the 3GPP access from the context for each bearer shown in FIG. Good.

  The UE_A 10 and the PGW_A 30 first compare the corresponding Routing Filter with the user data in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A10 and PGW_A30 compare the user data to be transmitted with the Routing Filter in the order of Filter B1 and Filter B2.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter B2, UE_A10 and PGW_A30 may transmit user data using Dedicated Bearer B2 corresponding to Filter B2.

  If the user data does not match any Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit the user data using the default bearer. For example, when user data to be transmitted does not match Filter B1 and Filter B2, UE_A 10 and PGW_A 30 may transmit user data using Default Bearer 2 which is a default bearer of the WLAN access network.

  Next, a second example will be described. Note that the context for the communication path by the WLAN access of the UE_A 10 and the PGW_A 30 in the second example may be one obtained by deleting the context for the communication path by the 3GPP access from the context for each bearer shown in FIG. Good.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare user data to be transmitted with Routing Filter in the order of Filter B 1, Filter B 2, ANY 2. Here, ANY 2 may be a filter in which a rule that matches all user data is described.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter B2, UE_A 10 transmits user data using Dedicated Bearer B2 corresponding to Filter B2. When the user data to be transmitted matches ANY 2, UE_A 10 may transmit user data using Default Bearer 2 corresponding to ANY 2.

  Next, a third example will be described. Note that the context for the communication path by the WLAN access of the UE_A 10 and the PGW_A 30 in the third example may be the context for each bearer shown in FIG. 17 from which the context for the communication path by the 3GPP access is deleted. Good.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A10 and PGW_A30 compare the user data to be transmitted with the Routing Filter in the order of Filter B1, Filter B2, and Filter D2. Here, Filter D2 may be a filter in which a rule that matches all user data corresponding to a specific UE_A10 and / or PGW_A30 is described. For example, Filter D2 may be a filter in which a rule that matches the source IP address of UE_A10 and / or PGW_A30 is described.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter B2, UE_A 10 transmits user data using Dedicated Bearer B2 corresponding to Filter B2. When the user data to be transmitted matches Filter D2, UE_A 10 may transmit the user data using Default Bearer 2 corresponding to Filter D2.

  In the example of the UE-initiated PDN connection disconnection procedure (3GPP access network), the case has been described where only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[1.4.4. Explanation of network-led PDN connection disconnection procedure (3GPP access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by a network will be described with reference to FIG.

  The PCRF_A 60 and the PGW_A 30 may detect the deterioration of the radio wave state of the 3GPP access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, PCRF_A60 and PGW_A30 may start the PDN connection disconnection procedure at an arbitrary timing.

  First, the PCRF_A 60 transmits a message for requesting an IP-CAN update procedure to the PGW_A 30 in order to start the PDN connection disconnection procedure (S2102). The message for requesting the IP-CAN update procedure may include at least first identification information and / or third identification information.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the message for requesting the IP-CAN update procedure transmitted by the PCRF_A 60. The PGW_A 30 receives the message for requesting the IP-CAN update procedure and / or the SGW_A 35 based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. A session deletion request is transmitted to (S2104).

  The PGW_A 30 receives at least the message for requesting the IP-CAN update procedure and / or at least based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. The first identification information and / or the third identification information may be included in the session deletion request and transmitted.

  Note that the method of starting the PDN connection disconnection procedure is not limited to the method of starting PCRF_A 60 in the IP-CAN session update procedure described so far, and PGW_A 30 may start. At this time, the PGW_A 30 may generate the first identification information and / or the third identification information, and transmit it by including it in the session deletion request.

  The SGW_A 35 receives the session deletion request transmitted by the PGW_A 30. The SGW_A 35 transmits the session deletion request to the MME_A 40 based on the reception of the session deletion request and / or the first identification information and / or the third identification information included in the session deletion request (S2106).

  The SGW_A 35 receives at least the first identification information and / or the third identification information in the session deletion request based on the first identification information and / or the third identification information included in the reception of the session deletion request and / or the session deletion request. You may include and send it.

  The MME_A 40 receives the session deletion request transmitted by the SGW_A 35. The MME_A 40 receives the session deletion request and / or transmits an EPS bearer context deactivation request (Deactivate EPS Bearer context request) to the eNB_A 45 based on the first identification information and / or the third identification information included in the session deletion request. (S2108). The EPS bearer context deactivation request may be a message for requesting deletion of the transfer path.

  The MME_A 40 receives at least a protocol discriminator and an EPS bearer identity based on the first identification information and / or the third identification information included in the reception of the session deletion request and / or the session deletion request. ), Procedure transaction identity (EPS), Deactivate EPS Bearer context request message identity (EMS) and EMS Couse are included in the EPS bearer context deactivation request. good. Further, the MME_A 40 may include at least the first identification information and / or the third identification information in the EPS bearer context deactivation request. Further, the MME_A 40 may include Protocol Configuration Options (PCO) and / or T3396 value (T3396 value) and / or WLAN Offload Indication in the EPS bearer context deactivation request.

  Here, the protocol discriminator may be information for identifying the type of protocol.

  The EPS bearer ID may be information for identifying a bearer.

  The procedure transaction ID may be information for identifying a PDN connection disconnection procedure.

  The EPS bearer context deactivation request message ID may be a message type representing an EPS bearer context deactivation request message.

  The EMS Cause may be information indicating the reason for transmitting the EPS bearer context deactivation request.

  The PCO may be protocol information associated with the PDN connection. Further, the UE_A 10 may include request identification information in the PCO. The MME_A 40 may transmit the first identification information and / or the third identification information included in the PCO.

  The T3396 value may be the value of the T3396 timer included when the ESM Cause represents an insufficient resource.

  The WLAN offload information may be information indicating whether traffic can be offloaded to the WLAN access network in the current PDN connection.

  eNB_A45 receives the EPS bearer context deactivation request transmitted by MME_A40. The eNB_A 45 transfers the EPS bearer context deactivation request to the UE_A 10 based on the reception of the EPS bearer context deactivation request.

  eNB_A45 may transmit an RRC connection configuration request (RRC Connection Reconfiguration) at least to UE_A10 together with the EPS bearer context deactivation request (S2110).

  UE_A10 receives the RRC connection setting request transmitted by eNB_A45. Furthermore, UE_A10 receives the EPS bearer context deactivation request transmitted by MME_A40 and transferred by eNB_A45.

  UE_A10 transmits RRC connection setting completion (RRC Connection Reconfiguration Complete) to eNB_A45 based on reception of the RRC connection setting request (S2112).

  eNB_A45 receives the RRC connection setup completion transmitted by UE_A10. The eNB_A 45 transmits a Deactivate Bearer Response to the MME 40 based on the completion of the RRC connection setting (S2114).

  The MME 40 receives the deactive bearer response transmitted by the eNB 45.

  The UE_A 10 receives the EPS bearer context deactivation request and / or the EPS bearer context deactivation to the MME_A 40 via the eNB_A 45 based on the first identification information and / or the third identification information included in the EPS bearer context deactivation request. An activation acceptance (Deactivate EPS Bearer context accept) is transmitted (S2116) (S2118). The EPS bearer context deactivation acceptance may be a control message indicating that the disconnection of the PDN connection is permitted. Further, the EPS bearer context deactivation acceptance message may be a response message to the EPS bearer context deactivation request.

  The UE_A 10 includes at least the protocol discriminator, the EPS bearer ID, the procedure transaction ID, and the EPS bearer context accept message identity (Activate default EPS bearer context accept message identity) in the EPS bearer context deactivation acceptance. You may send it. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the EPS bearer context deactivation acceptance. In addition, the PCO may be included in the EPS bearer context deactivation acceptance. Note that the UE_A 10 may transmit the first identification information and / or the second identification information included in the PCO.

  Here, the second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the second identification information, it may be indicated that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  The EPS bearer context deactivation acceptance message ID may be a message type representing an EPS bearer context deactivation acceptance message.

  The UE_A 10 receives the EPS bearer context deactivation request and / or transmits the EPS bearer context deactivation acceptance and / or the first identification information and / or the third identification information included in the EPS bearer context deactivation request and Alternatively, when the bearer identified by the EPS bearer ID is a default bearer based on the EPS bearer ID, the communication path by 3GPP access associated with the multi-access PDN connection associated with the default bearer identified by the EPS bearer ID You may cut only. More specifically, the UE_A 10 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection. Note that, when the bearer identified by the received EPS bearer ID is not the default bearer, the UE_A 10 does not have to disconnect the communication path by the 3GPP access.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, the UE_A 10 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, the UE_A 10 receives the EPS bearer context deactivation request and / or the first identification information and / or the third identification information and / or the EPS bearer ID and / or the EPS bearer context included in the EPS bearer context deactivation request. If the bearer identified by the EPS bearer ID is the default bearer based on the transmission of the deactivation acceptance, the default access associated with the multi-access PDN connection associated with the default bearer identified by the EPS bearer ID is It may be deleted. Note that when the bearer identified by the received EPS bearer ID is not the default bearer, the UE_A 10 does not have to delete the default access.

  In this way, the UE_A 10 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  The MME_A 40 receives the EPS bearer context deactivation acceptance transmitted by the UE_A 10. The MME_A 40 receives the EPS bearer context deactivation acceptance and / or transmits a session deletion response to the SGW_A 35 based on the first identification information and / or the second identification information included in the EPS bearer context deactivation acceptance (S2120). ). Note that it may be a response message to the session deletion request.

  The MME_A 40 receives at least the first identification information and / or the second identification information based on the reception of the EPS bearer context deactivation acceptance and / or the first identification information and / or the second identification information included in the acceptance of the EPS bearer context deactivation. May be included in the session deletion response and transmitted. Furthermore, the MME_A 40 may include a PDN connection ID (PDN connection ID) in the session deletion response.

  Here, the PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  The SGW_A 35 receives the session deletion response transmitted by the MME_A 40. The SGW_A 35 transmits the session deletion response to the PGW_A 30 based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response (S2122).

  The SGW_A 35 receives at least the first identification information and / or the second identification information in the session deletion response based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. You may include and transmit. Further, the SGW_A 35 may include a PDN connection ID (PDN connection ID) in the session deletion response.

  The PGW_A 30 receives the session deletion response transmitted by the SGW_A 35. The PGW_A 30 transmits a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. (S2124).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. It may be transmitted by being included in a message for notifying completion of the procedure.

  When the PGW_A 30 starts the PDN connection disconnection procedure instead of the PCRF_A 60, the PGW_A 30 may not transmit a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure.

  The PGW_A 30 receives a session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or first identification information and / or second identification information and / or PDN connection included in the session deletion response Based on the ID, only the communication path by the 3GPP access associated with the multi-access PDN connection identified by the PDN connection ID may be disconnected. More specifically, the PGW_A 30 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Accordingly, the PGW_A 30 receives the session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or the first identification information and / or the second identification information included in the session deletion response and / or Based on the PDN connection ID, the default access associated with the multi-access PDN connection identified by the PDN connection ID may be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  Further, the UE_A 10 receives the EPS bearer context deactivation request and / or accepts the first identification information and / or the third identification information included in the EPS bearer context deactivation request and / or the EPS bearer context deactivation acceptance. Based on the transmission, a signaling connection release procedure may be executed with the MME_A 40 (S2126). Further, the MME_A 40 performs signaling with the UE_A 10 based on reception of the EPS bearer context deactivation acceptance and / or transmission of the first identification information and / or the second identification information included in the EPS bearer context deactivation acceptance. A connection release procedure may be performed.

  Upon completion of the network-initiated PDN connection disconnection procedure (3GPP access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path by 3GPP access. The multi-access PDN connection that does not have a communication path by 3GPP access may be a multi-access PDN connection that has only a communication path by WLAN access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by WLAN access. Therefore, when there is a multi-access PDN connection having only a communication path by WLAN access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After completion of the network-driven PDN connection disconnection procedure (3GPP access network), the UE_A 10 and the PGW_A 30 may transmit / receive user data based on the stored context for the communication path by the WLAN access.

  Note that the UE_A 10 and PGW_A 30 that transmit and receive user data after the completion of the network-initiated PDN connection disconnection procedure (3GPP access network) is the same as the UE-initiated PDN connection disconnection procedure (3GPP access) described in Chapter 1.4.3. Network) It may be the same as the method of transmission / reception after completion. Therefore, the description of the user data transmission / reception method is omitted here.

  In the example of the network-driven PDN connection disconnection procedure (3GPP access network), a case has been described in which only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[1.4.5. Explanation of UE-led detachment procedure (3GPP access network)]
Next, an example of a detach procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by UE will be described with reference to FIG.

  Note that the UE_A 10 may detect the deterioration of the radio wave state of the 3GPP access system or the instability of the connectivity, and start the detach procedure. Further, the UE_A 10 may start the detach procedure at an arbitrary timing.

  The UE_A 10 first transmits a detach request to the MME_A 40 via the eNB_A 45 (S2202). The UE_A 10 includes at least a protocol discriminator, a security header type, a detach request message ID, a detach type, and an EPS mobile identity (EPS mobile identity). ) Including the detach request may be transmitted. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the detach request.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  Thus, by transmitting the first identification information and / or the second identification information, it may be requested to disconnect only the communication path by 3GPP access associated with the multi-access PDN connection. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is requested to be disconnected.

  The protocol discriminator may be information for identifying the type of protocol.

  The security header type may be security information used in the NAS message.

  The detach request message ID may be a message type representing a detach request message.

  The detach type may be information for identifying the type of detach procedure requested.

  The EPS mobile ID is information for identifying the UE_A 10.

  MME_A40 receives the detach request transmitted by UE_A10. The MME_A 40 receives the detach request and / or transmits a session deletion request to the SGW_A 35 based on the first identification information and / or the second identification information included in the detach request (S2204). The session deletion request may be a message for requesting deletion of the transfer path.

  The MME_A 40 includes at least the first identification information and / or the second identification information in the session deletion request based on the first identification information and / or the second identification information included in the reception of the detach request and / or the detach request. You may send it. Further, the MME_A 40 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  MME_A 40 deletes the session without including the first identification information and / or the second identification information when neither the first identification information nor the second identification information is included in the detach request. A request may be sent.

  Here, the PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  The SGW_A 35 receives the session deletion request transmitted by the MME_A 40. The SGW_A 35 receives the session deletion request and / or transmits a session deletion request to the PGW_A 30 based on the first identification information and / or the second identification information included in the session deletion request (S2206).

  The SGW_A 35 receives at least the first identification information and / or the second identification information in the session deletion request based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. You may include and transmit. Further, the SGW_A 35 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  Note that the SGW_A 35 does not include the first identification information and / or the second identification information when the session deletion request does not include the first identification information and / or the second identification information. A delete request may be sent.

  The PGW_A 30 receives the session deletion request transmitted by the SGW_A 35. The PGW_A 30 may execute an IP-CAN session update procedure with the PCRF_A 60 based on the reception of the session deletion request and / or the first identification information and / or the second identification information included in the session deletion request. (S2208).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. It may be executed as part of the update procedure.

  Note that the PGW_A 30 may execute the IP-CAN session update procedure to notify the PCRF_A 60 that only the 3GPP access communication path associated with the multi-access PDN connection is to be disconnected.

  The PGW_A 30 includes information indicating whether the communication path to be deleted is a communication path associated with a multi-access PDN connection or a communication path associated with a single access PDN connection, and / or first identification information and / or The identification information 2 may be included in a control message in the IP-CAN session procedure and transmitted to the PCRF_A 60.

  More specifically, when the communication channel to be deleted is a communication channel associated with the multi-access PDN connection, the PGW_A 30 indicates that information indicating the 3GPP access network and that the PDN connection is a multi-access PDN connection. The information to be shown and the first identification information and / or the second identification information are transmitted to the PCRF_A 60. Alternatively, when the communication path to be deleted is a communication path associated with the single access PDN connection, the PGW_A 30 includes information indicating the 3GPP access network and information indicating that the PDN connection is a single access PDN connection. It transmits to PCRF_A60.

  Further, the PCRF_A 60 receives at least the first identification information and / or the third identification information in the control message in the IP-CAN session update procedure with the PGW_A 30 based on the reception of the first identification information and / or the second identification information. You may transmit to PGW_A30 including identification information.

  The PCRF_A 60 may execute an IP-CAN session update procedure in order to notify the PGW_A 30 of charging information and / or QoS control information and / or routing information.

  Here, the third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the session deletion request or completes the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the first identification information included in the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, a session deletion response is transmitted to the SGW_A 35 (S2210).

  The PGW_A 30 is included in the reception of the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, at least the first identification information and / or the third identification information may be included in the session deletion response and transmitted.

  Note that the method of acquiring the third identification information by the PGW_A 30 is not limited to the method of acquiring from the PCRF_A 60 in the IP-CAN session update procedure described so far, and may be another example. For example, the PGW_A 30 may not acquire from the PCRF_A 60 in the IP-CAN session update procedure, and the PGW_A 30 may generate the third identification information and transmit it by including it in the session deletion response.

  The PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits a session deletion response and / or first identification information and / or second identification information included in the session deletion request and / or Communication by 3GPP access associated with the multi-access PDN connection identified by the PDN connection ID based on the PDN connection ID and / or the first identification information and / or the third identification information included in the IP-CAN session update procedure Only the road may be cut. More specifically, the PGW_A 30 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Therefore, the PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits the session deletion response and / or the first identification information and / or the second identification information included in the session deletion request. And / or the default access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the IP-CAN session update procedure. May be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  The SGW_A 35 receives the session deletion response transmitted by the PGW_A 30. The SGW_A 35 transmits the session deletion response to the MME_A 40 based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response (S2212).

  The PGW_A 30 receives at least the first identification information and / or the third identification information in the session deletion response based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. You may include and send it.

  The MME_A 40 receives the session deletion response transmitted by the SGW_A 35. Based on the first identification information and / or the third identification information included in the session deletion response and / or the session deletion response, the MME_A 40 transmits a detach acceptance to the UE_A 10 via the eNB_A 45 (S2214). The detach acceptance message may be a control message indicating that disconnection of the PDN connection is permitted, and may be an EPS bearer context deactivation request (Deactivate EPS Bearer context request). Further, the detach acceptance message may be a response message to the detach request.

  The MME_A 40 receives at least the protocol discriminator, the security header type, and the detach acceptance message ID (Detach accept message ID) based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. message identity) may be included in the detach acceptance. Further, the MME_A 40 may include at least the first identification information and / or the third identification information in the detach acceptance.

  Here, the detach acceptance message ID may be a message type representing a detach acceptance message.

  UE_A10 receives the detach acceptance transmitted by MME_A40.

  The UE_A 10 associates the multi-access PDN connection with the reception of the detach acceptance and / or the first identification information and / or the third identification information included in the detach acceptance and / or the information from which access network the detach acceptance is transmitted. Only the communication path by the 3GPP access that has been made may be disconnected. More specifically, the UE_A 10 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, the UE_A 10 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Accordingly, the UE_A 10 can receive the multi-access PDN connection based on the first identification information and / or the third identification information included in the detach acceptance and / or the information from which access network the detach acceptance was transmitted. The associated default access may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  Further, the UE_A 10 may execute a signaling connection release procedure with the MME_A 40 based on the reception of the detach acceptance and / or the reception of the first identification information and / or the third identification information included in the detach acceptance ( S2216). In other words, the MME_A 40 may perform a signaling connection release procedure with the UE_A 10 based on the transmission of the detach acceptance and / or the transmission of the first identification information and / or the third identification information included in the detach acceptance. .

  Upon completion of the UE-initiated detach procedure (3GPP access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for 3GPP access. The multi-access PDN connection that does not have a communication path by 3GPP access may be a multi-access PDN connection that has only a communication path by WLAN access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when there is a multi-access PDN connection having only a communication path by WLAN access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After the UE-initiated detach procedure (3GPP access network) is completed, the UE_A 10 and the PGW_A 30 may transmit and receive user data based on the stored context for the communication path by the WLAN access.

  The UE_A10 and PGW_A30 transmitting / receiving user data after completion of the UE-initiated detach procedure (3GPP access network) is described in Chapter 1.4.3, UE-initiated PDN connection disconnection procedure (3GPP access network). The transmission / reception method after completion may be the same. Therefore, the description of the user data transmission / reception method is omitted here.

  In the example of the UE-initiated detach procedure (3GPP access network), the case has been described where only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[1.4.6. Explanation of network-driven detachment procedure (3GPP access network)]
Next, an example of a detach procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by a network will be described with reference to FIG.

  Note that the MME_A 40 may detect the deterioration of the radio wave state of the 3GPP access system or the instability of the connectivity, and start the detach procedure. Further, the MME_A 40 may start the detach procedure at an arbitrary timing.

  First, the MME_A 40 transmits a detach request to the UE_A 10 via the eNB_A 45 (S2302). The MME_A 40 includes at least a protocol discriminator, a security header type, a detach request message ID, a detach type, and a spare half octet. ) Including the detach request may be transmitted. Further, the UE_A 10 may include at least the first identification information and / or the third identification information in the detach request. Further, the EMS Cause may be transmitted by being included in the detach request. The detach request may be a message for requesting disconnection of the PDN connection.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be requested to disconnect only the communication path by 3GPP access associated with the multi-access PDN connection. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is requested to be disconnected.

  The protocol discriminator may be information for identifying the type of protocol.

  The security header type may be security information used in the NAS message.

  The detach request message ID may be a message type representing a detach request message.

  The detach type may be information for identifying the type of detach procedure requested.

  The spare half octet may be an element for filling a vacant bit.

  The EMS Cause may be information indicating the reason for transmitting the EPS bearer context deactivation request.

  UE_A10 receives the detach request transmitted by MME_A40.

  The MME_A 40 transmits a detach request and / or transmits a session deletion request to the SGW_A 35 based on the first identification information and / or the third identification information included in the detach request (S2304). The session deletion request may be a message for requesting deletion of the transfer path.

  The MME_A 40 includes at least the first identification information and / or the second identification information in the session deletion request based on the first identification information and / or the third identification information included in the transmission of the detach request and / or the detach request. You may send it. Further, the MME_A 40 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  Here, the second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  Thus, by transmitting the first identification information and / or the second identification information, it may be requested to disconnect only the communication path by 3GPP access associated with the multi-access PDN connection. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by 3GPP access associated with the multi-access PDN connection is requested to be disconnected.

  Here, the PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  MME_A 40 deletes the session without including the first identification information and / or the second identification information when neither the first identification information nor the third identification information is included in the detach request. A request may be sent.

  The SGW_A 35 receives the session deletion request transmitted by the MME_A 40. The SGW_A 35 receives the session deletion request and / or transmits a session deletion request to the PGW_A 30 based on the first identification information and / or the second identification information included in the session deletion request (S2306).

  The SGW_A 35 receives at least the first identification information and / or the second identification information in the session deletion request based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. You may include and transmit. Further, the SGW_A 35 may include a PDN connection ID (PDN connection ID) in the session deletion request.

  Note that the SGW_A 35 does not include the first identification information and / or the second identification information when the session deletion request does not include the first identification information and / or the second identification information. A delete request may be sent.

  The PGW_A 30 receives the session deletion request transmitted by the SGW_A 35. The PGW_A 30 may execute an IP-CAN session update procedure with the PCRF_A 60 based on the reception of the session deletion request and / or the first identification information and / or the second identification information included in the session deletion request. (S2308).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. It may be executed as part of the update procedure.

  Note that the PGW_A 30 may execute the IP-CAN session update procedure to notify the PCRF_A 60 that only the 3GPP access communication path associated with the multi-access PDN connection is to be disconnected.

  The PGW_A 30 includes information indicating whether the communication path to be deleted is a communication path associated with a multi-access PDN connection or a communication path associated with a single access PDN connection, and / or first identification information and / or The identification information 2 may be included in a control message in the IP-CAN session procedure and transmitted to the PCRF_A 60.

  More specifically, when the communication channel to be deleted is a communication channel associated with the multi-access PDN connection, the PGW_A 30 indicates that information indicating the 3GPP access network and that the PDN connection is a multi-access PDN connection. The information to be shown and the first identification information and / or the second identification information are transmitted to the PCRF_A 60. Alternatively, when the communication path to be deleted is a communication path associated with the single access PDN connection, the PGW_A 30 includes information indicating the 3GPP access network and information indicating that the PDN connection is a single access PDN connection. It transmits to PCRF_A60.

  Further, the PCRF_A 60 receives at least the first identification information and / or the third identification information in the control message in the IP-CAN session update procedure with the PGW_A 30 based on the reception of the first identification information and / or the second identification information. You may transmit to PGW_A30 including identification information.

  The PCRF_A 60 may execute an IP-CAN session update procedure in order to notify the PGW_A 30 of charging information and / or QoS control information and / or routing information.

  Here, the PGW_A 30 receives the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the included first identification information and / or third identification information, a session deletion response is transmitted to SGW_A 35 (S2310).

  The PGW_A 30 is included in the reception of the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, at least the first identification information and / or the third identification information may be included in the session deletion response and transmitted.

  Note that the method of acquiring the third identification information by the PGW_A 30 is not limited to the method of acquiring from the PCRF_A 60 in the IP-CAN session update procedure described so far, and may be another example. For example, the PGW_A 30 may not acquire from the PCRF_A 60 in the IP-CAN session update procedure, and the PGW_A 30 may generate the third identification information and transmit it by including it in the session deletion response.

  The PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits a session deletion response and / or first identification information and / or second identification information included in the session deletion request and / or Communication by 3GPP access associated with the multi-access PDN connection identified by the PDN connection ID based on the PDN connection ID and / or the first identification information and / or the third identification information included in the IP-CAN session update procedure Only the road may be cut. More specifically, the PGW_A 30 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Therefore, the PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits the session deletion response and / or the first identification information and / or the second identification information included in the session deletion request. And / or the default access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the IP-CAN session update procedure. May be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  The SGW_A 35 receives the session deletion response transmitted by the PGW_A 30. The SGW_A 35 transmits the session deletion response to the MME_A 40 based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response (S2312).

  The PGW_A 30 receives at least the first identification information and / or the third identification information in the session deletion response based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. You may include and send it.

  The MME_A 40 receives the session deletion response transmitted by the SGW_A 35.

  The UE_A 10 receives the detach request and / or transmits a detach acceptance to the MME_A 40 via the eNB_A 45 based on the first identification information and / or the third identification information included in the detach request (S2314). The detach acceptance message may be a control message indicating that disconnection of the PDN connection is permitted, and may be an EPS bearer context deactivation request (Deactivate EPS Bearer context request). Further, the detach acceptance message may be a response message to the detach request.

  The UE_A 10 receives the detach request and / or based on the first identification information and / or the third identification information included in the detach request, at least the protocol discriminator, the security header type, and the detach acceptance message ID (Detach accept message identity) may be included in the detach acceptance and sent. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the detach acceptance.

  Here, the detach acceptance message ID may be a message type representing a detach acceptance message.

  The MME_A 40 receives the detach acceptance transmitted by the UE_A 10.

  The UE_A 10 receives the detach request and / or transmits the detach acceptance and / or the first identification information and / or the third identification information included in the detach request and / or information on which access network the detach request is transmitted from. Only the communication path by 3GPP access associated with the multi-access PDN connection may be disconnected. More specifically, the UE_A 10 may disconnect the communication path for 3GPP access by deleting the context for the communication path for 3GPP access associated with the multi-access PDN connection.

  Further, when all the communication paths by 3GPP access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, the UE_A 10 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the 3GPP access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, the UE_A 10 receives the detach request and / or transmits the detach acceptance and / or the first identification information and / or the third identification information included in the detach request and / or information on which access network the detach request is transmitted from. Thus, the default access associated with the multi-access PDN connection may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the 3GPP access associated with the multi-access PDN connection by deleting the context for the communication path by the 3GPP access associated with the multi-access PDN connection and / or the default access. May be.

  Further, the UE_A 10 releases the signaling connection with the MME_A 40 based on the reception of the detach request and / or the transmission of the detach acceptance and / or the reception of the first identification information and / or the third identification information included in the detach request. The procedure may be executed (S2316). In other words, the MME_A 40 may perform a signaling connection release procedure with the UE_A 10 based on reception of the detach acceptance and / or transmission of the first identification information and / or the second identification information included in the detach acceptance. .

  Upon completion of the network-led detach procedure (3GPP access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for 3GPP access. The multi-access PDN connection that does not have a communication path by 3GPP access may be a multi-access PDN connection that has only a communication path by WLAN access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when there is a multi-access PDN connection having only a communication path by WLAN access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After completion of the network-driven detach procedure (3GPP access network), the UE_A 10 and the PGW_A 30 may transmit / receive user data based on the stored context for the communication path by the WLAN access.

  The UE_A10 and PGW_A30 transmitting / receiving user data after completion of the UE-initiated detach procedure (3GPP access network) is described in Chapter 1.4.3, UE-initiated PDN connection disconnection procedure (3GPP access network). The transmission / reception method after completion may be the same. Therefore, the description of the user data transmission / reception method is omitted here.

  In the example of the network-driven detach procedure (3GPP access network), the case where only the communication path by 3GPP access associated with the multi-access PDN connection is disconnected has been described.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[2. Second Embodiment]
Hereinafter, a wireless communication technique according to an embodiment of the present invention will be described in detail with reference to the drawings.

[2.1. System overview]
The outline of the mobile communication system in the present embodiment may be obtained by replacing TWAG_A74 with ePDG_A65 in the mobile communication system described with reference to FIG. 1 in the first embodiment. Further, in the first embodiment, the access network B is WLAN_ANA 70, whereas in this embodiment, the access network B may be WLAN_ANb75.

  The access network A, the core network_A 90, and each device in FIG. 1 excluding the TWAG_A 74 and the access network B may be the same as those in the first embodiment. Further, also in this embodiment, the NBIOM similar to the first embodiment is a technology capable of establishing a multi-access PDN connection, and the description of the NBIOM and the multi-access PDN connection is the movement of the first embodiment. Since it is as having demonstrated by the schematic description of the communication system, detailed description is abbreviate | omitted.

  Furthermore, the configuration of the core network_A90, the configuration of the IP mobile communication network 5, the configuration of the UE_A10, and the configuration of the PDN_A100 are the same as those described with reference to FIGS. 2A and 2B in the first embodiment. It may be. Therefore, detailed description is omitted.

[2.2. Device configuration]
Hereinafter, the configuration of each apparatus will be described.

[2.2.1. ePDG configuration]
The configuration of ePDG_A65 in the present embodiment may be the same as the configuration of ePDG described in section 1.2.6 of the first embodiment. Therefore, detailed description is omitted.

[2.2.2. HSS configuration]
The configuration of the HSS_A 50 in the present embodiment may be the same as the configuration of the HSS described in Chapter 1.2.2 of the first embodiment. Therefore, detailed description is omitted.

[2.2.3. UE configuration]
The configuration of the UE_A 10 in the present embodiment may be the same as the configuration of the UE described with reference to FIG. 7 in Chapter 1.2.3 of the first embodiment. However, UE_A 10 may store ePDG capability in UE context A 752 instead of storing TWAG capability.

  Note that the ePDG Capability stores identification information (NBIFOM Capability) indicating whether the ability to establish the first PDN connection is supported for each ePDG. In other words, the identification information indicates whether or not the ePDG_A 65 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A65 is a gateway having a function of establishing a first PDN connection. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A 65 is a gateway that supports the NBIOM function.

  The UE_A 10 may store NBIOM Capability in association with the ePDG ID. Further, NBIOM Capabilities for a plurality of ePDGs may be stored.

  In addition, each information element other than the functional units such as the LTE interface unit _A 720, the WLAN interface unit _A 740, the control unit _A 700, the storage unit _A 750, and the TWAG capability of the UE context A 752 is 1.2 of the first embodiment. .Since it may be the same as each functional unit and each information element described with reference to FIGS. 7 and 8 in Chapter 3, detailed description will be omitted.

  Also in this embodiment, as in the first embodiment, the PDN connection ID is identification information for identifying a PDN connection. UE_A10, ePDG_A65, and PGW_A30 may store the same identification information.

[2.2.4. PGW configuration]
The configuration of the PGW_A 30 in the present embodiment may be the same as the configuration of the PGW described with reference to FIG. 9 in Chapter 1.2.4 of the first embodiment. However, PGW_A30 may store ePDG capability instead of storing TWAG capability in EPS bearer context A942.

  Note that the ePDG Capability stores identification information (NBIFOM Capability) indicating whether the ability to establish the first PDN connection is supported for each ePDG. In other words, the identification information indicates whether or not the ePDG_A 65 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A65 is a gateway having a function of establishing a first PDN connection. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A 65 is a gateway that supports the NBIOM function.

  The PGW_A 30 may store the NBIOM capability in association with the ePDG ID. Further, NBIOM Capabilities for a plurality of ePDGs may be stored.

  In addition, each functional element such as the network connection unit _A 920, the control unit _A 900, the storage unit _A 940, and the TWAG capability of the EPS bearer context A 942 is illustrated in chapter 1.2.4 of the first embodiment. 9 and 10 may be the same as the functional units and information elements described with reference to FIG.

  Also in this embodiment, as in the first embodiment, the PDN connection ID is identification information for identifying a PDN connection. UE_A10, ePDG_A65, and PGW_A30 may store the same identification information.

[2.2.5. PCRF configuration]
The configuration of PCRF_A 60 in the present embodiment may be the same as the configuration of the UE described with reference to FIG. 11 in section 1.2.5 of the first embodiment. However, PCRF_A 60 may store ePDG capability in UE context A 1142 instead of storing TWAG capability.

  Note that the ePDG Capability stores identification information (NBIFOM Capability) indicating whether the ability to establish the first PDN connection is supported for each ePDG. In other words, the identification information indicates whether or not the ePDG_A 65 supports the NBIOM function. Specifically, NallowM Capability may include “allowed” or “Not allowed”.

  Note that the NBIOM function may be information indicating that a multi-access PDN connection is established.

  Alternatively, the NBIOM capability may be identification information indicating that the first PDN connection is capable of being established. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A65 is a gateway having a function of establishing a first PDN connection. In other words, the presence of NBIOM capability in the storage unit may mean that ePDG_A 65 is a gateway that supports the NBIOM function.

  The PCRF_A 60 may store NBIOM Capability in association with the ePDG ID. Further, NBIOM Capabilities for a plurality of ePDGs may be stored.

  In addition, each information element excluding each function unit such as the network connection unit_A1120, the control unit_A1100, the storage unit_A1140, and the TWAG capability of the UE context A1142, is described in Chapter 1.2.4 of the first embodiment. Since it may be the same as each functional unit and each information element described with reference to FIG.

[2.3. Explanation of the initial state]
The initial state in this embodiment will be described. An example of the initial state in the present embodiment will be described with reference to FIG.

  As described above, in this embodiment, TWAG_A 74 in FIG. 1 is ePDG_A 65, and access network B is Untrusted Non-3GPP Access Network. Furthermore, ePDG_A65 is a gateway device that is arranged in the core network_A90 and connects the access network B and the core network_A90.

  In the initial state in the present embodiment, the UE_A 10 is in a state where a multi-access PDN connection is established with the core network_A 90 via the access network A and the access network B. Specifically, the UE_A 10 establishes a multi-access PDN connection that establishes a communication path by 3GPP access and a communication path by WLAN with the PGW_A 30 included in the core network_A 90. Here, 3GPP access may be an access system that is not WLAN access. More specifically, it may be information indicating an access network including E-UTRAN access, UTRAN access, and GERAN access.

  The communication path by 3GPP access is a communication path established between the UE_A 10 and the PGW_A 30 included in the core network_A 90 via the LTE base station eNB_A 45 included in the access network A and the SGW_A 35 included in the core network_A 90. It's okay. In other words, the communication path by 3GPP access is a communication path configured by a transfer path between UE_A10 and eNB_A45, a transfer path between eNB_A45 and SGW_A35, and a transfer path between SGW_A35 and PGW_A30. Also good. Moreover, the communication path by 3GPP access may be comprised by the bearer.

  The UE_A 10 and the PGW_A 30 may establish a plurality of 3GPP access communication paths associated with the multi-access PDN connection. Note that the UE_A 10 and the PGW_A 30 may use the first established transfer path as a default bearer among a plurality of 3GPP access communication paths associated with the multi-access PDN connection. Note that UE_A 10 and PGW_A 30 may store a default bearer in association with information for identifying 3GPP access.

  The communication path by the WLAN access may be a communication path established between the UE_A 10 and the PGW_A 30 included in the core network_A 90 via the ePDG_A 65. In other words, the communication path by WLAN access may be a communication path configured by a transfer path between UE_A10 and ePDG_A65 and a transfer path between ePDG_A65 and PGW_A30. Moreover, the communication path by WLAN access may be comprised by the bearer. Moreover, the communication path by WLAN access may be comprised by transfer paths other than a bearer. In that case, the information for identifying the bearer may be information for identifying a transfer path other than the bearer.

  The UE_A 10 and the PGW_A 30 may establish communication paths using a plurality of WLAN accesses associated with the multi-access PDN connection. Note that the UE_A 10 and the PGW_A 30 may use the first established transfer path as a default bearer among a plurality of WLAN access communication paths associated with the multi-access PDN connection. Note that UE_A 10 and PGW_A 30 may store a default bearer in association with information for identifying WLAN access.

  UE_A10 and PGW_A30 may memorize | store the context for each communication path matched with the multi-access PDN connection. The context for each communication path associated with the multi-access PDN connection may include a communication path context by 3GPP access and a communication path context by WLAN access.

  The context for the communication path by 3GPP access includes the default bearer associated with the communication path by 3GPP access in FIGS. 8 and 10, the UE context and the EPS bearer context for each default bearer associated with the communication path by 3GPP access. And a UE context and an EPS bearer context for each Dedicated Bearer associated with a communication path by 3GPP access.

  The context for the communication path by the WLAN access includes the Default Bearer associated with the communication path by the WLAN access in FIGS. 8 and 10, the UE context and the EPS bearer context for each Default Bearer associated with the communication path by the WLAN access. And a UE context and an EPS bearer context for each Dedicated Bearer associated with a communication path by WLAN access.

  UE_A10 and PGW_A30 may transmit and receive user data based on the context for each communication path associated with the stored multi-access PDN connection. Further, when there are a plurality of default bearers associated with the multi-access PDN connection, the UE_A 10 and the PGW_A 30 are based on the default access associated with the context for each communication path associated with the multi-access PDN connection. A default bearer to be used may be selected.

  Further, the method of transmitting and receiving user data by the UE_A 10 and the PGW_A 30 in the initial state may be the same as the first to third examples shown in the description of the initial state in Chapter 1.3 of the first embodiment. Therefore, detailed description is omitted.

  Although the initial state has been described above, the initial state is not limited to this, and another PDN connection may be established as long as the UE_A 10 has established a multi-access PDN connection.

[2.4. Explanation of PDN connection disconnection procedure]
[2.4.1. Explanation of UE-led PDN connection disconnection procedure (WLAN access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by WLAN access associated with a multi-access PDN connection led by UE will be described with reference to FIG.

  Note that the UE_A 10 may detect the deterioration of the radio wave state of the WLAN access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, UE_A10 may start a PDN connection disconnection procedure at arbitrary timings.

  First, the UE_A 10 transmits an INFORMATIONAL request (INFORMATIONAL request) to the ePDG_A 65 in order to start the PDN connection disconnection procedure (S2402). The UE_A 10 may transmit an INFORMATIONAL request including at least a DELETE payload. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the INFORMATION request. Further, UE_A 10 may include a PDN connection ID (PDN connection ID) in the INFORMATION request.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the second identification information, it may be requested to disconnect only the communication path by the WLAN access associated with the multi-access PDN connection. In other words, the first identification information and / or the second identification information may be information indicating that it is requested to disconnect only the communication path by the WLAN access associated with the multi-access PDN connection.

  The deletion payload may be information included to indicate that a disconnection of a tunnel between UE_A10 and ePDG_A65 is requested. Therefore, the UE_A 10 may request disconnection of the PDN connection by including the deletion payload in the INFORMATION request. Note that the INFORMATIONAL request may be an IKEv2 message.

  The PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  ePDG_A65 receives the INFORMATIONAL request transmitted by UE_A10. The ePDG_A 65 receives the INFORMATION request and / or transmits a session deletion request to the PGW_A 30 based on the first identification information and / or the second identification information included in the INFORMATION request (S2404). The session deletion request may be a message for requesting deletion of the transfer path.

  The ePDG_A 65 includes at least the first identification information and / or the second identification information in the session deletion request based on the reception of the INFORMATION request and / or the first identification information and / or the second identification information included in the INFORMATION request. You may send it. Further, the ePDG_A 65 may include the PDN connection ID in the session deletion request.

  In addition, when the identification information of the first identification information and / or the second identification information is not included in the INFORMATION request, the ePDG_A65 deletes the session without including the first identification information and / or the second identification information. A request may be sent.

  The PGW_A 30 receives the session deletion request transmitted by the ePDG_A 65. The PGW_A 30 may execute an IP-CAN session update procedure with the PCRF_A 60 based on the reception of the session deletion request and / or the first identification information and / or the second identification information included in the session deletion request. (S2406).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the first identification information and / or the second identification information included in the reception of the session deletion request and / or the session deletion request. It may be executed as part of the update procedure.

  Note that the PGW_A 30 may execute the IP-CAN session update procedure in order to notify the PCRF_A 60 that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 includes information indicating whether the communication path to be deleted is a communication path associated with a multi-access PDN connection or a communication path associated with a single access PDN connection, and / or first identification information and / or The identification information 2 may be included in a control message in the IP-CAN session procedure and transmitted to the PCRF_A 60.

  More specifically, when the communication path to be deleted is a communication path associated with the multi-access PDN connection, the PGW_A 30 includes information indicating the WLAN access network, the PDN connection ID, and the PDN connection is the multi-access PDN. Information indicating the connection and the first identification information and / or the second identification information are transmitted to the PCRF_A 60. Alternatively, when the communication path to be deleted is a communication path associated with the single access PDN connection, the PGW_A 30 is information indicating the WLAN access network, the PDN connection ID, and the PDN connection is a single access PDN connection. Is sent to PCRF_A60.

  Further, the PCRF_A 60 receives at least the first identification information and / or the third identification information in the control message in the IP-CAN session update procedure with the PGW_A 30 based on the reception of the first identification information and / or the second identification information. You may transmit to PGW_A30 including identification information.

  The PCRF_A 60 may execute an IP-CAN session update procedure in order to notify the PGW_A 30 of charging information and / or QoS control information and / or routing information.

  Here, the third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the session deletion request or completes the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the first identification information included in the IP-CAN session update procedure. Based on the identification information 1 and / or the third identification information, a session deletion response is transmitted to the ePDG_A 65 (S2408).

  The PGW_A 30 is included in the reception of the session deletion request or the completion of the IP-CAN session update procedure and / or the first identification information and / or the second identification information included in the session deletion request and / or the IP-CAN session update procedure. Based on the first identification information and / or the third identification information, at least the first identification information and / or the third identification information may be included in the session deletion response and transmitted.

  Note that the method of acquiring the third identification information by the PGW_A 30 is not limited to the method of acquiring from the PCRF_A 60 in the IP-CAN session update procedure described so far, and may be another example. For example, the PGW_A 30 may not acquire from the PCRF_A 60 in the IP-CAN session update procedure, and the PGW_A 30 may generate the third identification information and transmit it by including it in the session deletion response.

  The PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits a session deletion response and / or first identification information and / or second identification information included in the session deletion request and / or Communication by WLAN access associated with the multi-access PDN connection identified by the PDN connection ID based on the PDN connection ID and / or the first identification information and / or the third identification information included in the IP-CAN session update procedure Only the road may be cut. More specifically, the PGW_A 30 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Therefore, the PGW_A 30 receives the session deletion request and / or completes the IP-CAN session update procedure and / or transmits the session deletion response and / or the first identification information and / or the second identification information included in the session deletion request. And / or the default access associated with the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information included in the IP-CAN session update procedure. May be deleted. In this way, the PGW_A 30 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  The PGW_A 30 is associated with the multi-access PDN connection based on the detection that the connectivity of the WLAN access system is lost due to the deterioration of the radio wave condition of the WLAN access system or the instability of the connectivity. The context for the communication path by the WLAN access and / or the default access may be deleted.

  The ePDG_A 65 receives the session deletion response transmitted by the PGW_A 30. The ePDG_A 65 transmits an INFORMATIONAL response (INFORMATIONAL response) to the UE_A 10 based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response (S2410). Note that the INFORMATION response message may be a control message indicating that the disconnection of the PDN connection is permitted. Further, the INFORMATION response message may be a response message to the INFORMATION request.

  The ePDG_A 65 may transmit the deleted security association list by including the deleted security association list in the INFORMATIONAL response based on the reception of the session deletion response and / or the first identification information and / or the third identification information included in the session deletion response. Further, the ePDG_A 65 may include at least the first identification information and / or the third identification information in the INFORMATION response. Further, the ePDG_A 65 may include the PDN connection ID in the INFORMATION response.

  Here, the deleted security association list may be information including a list of security associations disconnected by ePDG_A65. Note that the INFORMATION response may be an IKEv2 message.

  UE_A10 receives the INFORMATIONAL response transmitted by ePDG_A65.

  UE_A10 is associated with the multi-access PDN connection identified by the PDN connection ID based on the reception of the INFORMATION response and / or the first identification information and / or the third identification information and / or the PDN connection ID included in the INFORMATION response. Alternatively, only the communication path by WLAN access may be disconnected. More specifically, the UE_A 10 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, UE_A10 may delete the default access matched with the multi-access PDN connection, when all the contexts for the communication path by the WLAN access matched with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, UE_A10 corresponds to the multi-access PDN connection identified by the PDN connection ID based on the first identification information and / or the third identification information and / or the PDN connection ID included in the reception of the INFORMATION response and / or the INFORMATION response. The attached default access may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  The UE_A 10 is associated with the multi-access PDN connection based on the detection that the connectivity of the WLAN access system has been lost due to the deterioration of the radio wave condition of the WLAN access system or the instability of the connectivity. The context for the communication path by the WLAN access and / or the default access may be deleted.

  Upon completion of the UE-initiated PDN connection disconnection procedure (WLAN access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for WLAN access. The multi-access PDN connection that does not have a communication path by WLAN access may be a multi-access PDN connection that has only a communication path by 3GPP access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when having a multi-access PDN connection having only a communication path by 3GPP access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After the UE-initiated PDN connection disconnection procedure (WLAN access network) is completed, the UE_A 10 and the PGW_A 30 may transmit and receive user data based on the stored context for the communication path using 3GPP access.

  Next, first to third examples will be described as specific examples of a method in which UE_A 10 and PGW_A 30 transmit and receive user data after completion of the UE-led PDN connection disconnection procedure (WLAN access network).

  First, a first example will be described. Note that the context for the communication path by the 3GPP access of the UE_A 10 and the PGW_A 30 in the first example may be the context for each bearer shown in FIG. 15 from which the context for the communication path by the WLAN access is deleted. Good.

  The UE_A 10 and the PGW_A 30 first compare the corresponding Routing Filter with the user data in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare the user data to be transmitted with the Routing Filter in the order of Filter A 1 and Filter A 2.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A10 and PGW_A30 may transmit user data using Dedicated Bearer A2 corresponding to Filter A2.

  If the user data does not match any Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit the user data using the default bearer. For example, when user data to be transmitted does not match Filter A1 and Filter A2, UE_A10 and PGW_A30 may transmit user data using Default Bearer 1 which is a default bearer of the 3GPP access network.

  Next, a second example will be described. Note that the context for the communication path by 3GPP access of UE_A10 and PGW_A30 in the second example may be the context for each bearer shown in FIG. 16 from which the context for the communication path by WLAN access is deleted. Good.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A 10 and PGW_A 30 compare the user data to be transmitted with the Routing Filter in the order of Filter A 1, Filter A 2, ANY 1. Here, ANY 1 may be a filter describing a rule that matches all user data.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches ANY 1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to ANY 1.

  Next, a third example will be described. Note that the context for the communication path by the 3GPP access of the UE_A 10 and the PGW_A 30 in the third example may be obtained by deleting the context for the communication path by the WLAN access from the context for each bearer illustrated in FIG.

  Similar to the first example, the UE_A 10 and the PGW_A 30 first compare user data with the corresponding Routing Filter in descending order of the Routing Rule Priority. For example, when transmitting user data, UE_A10 and PGW_A30 compare the user data to be transmitted with the Routing Filter in the order of Filter A1, Filter A2, and Filter D1. Here, Filter D1 may be a filter in which a rule that matches all user data corresponding to a specific UE_A10 and / or PGW_A30 is described. For example, Filter D1 may be a filter in which a rule that matches the source IP address of UE_A10 and / or PGW_A30 is described.

  If the user data matches the Routing Filter as a result of the comparison, the UE_A 10 and the PGW_A 30 may transmit / receive the user data using the corresponding Routing Rule identifier and / or the bearer identified by the bearer identification information. For example, when user data to be transmitted matches Filter A2, UE_A 10 transmits user data using Dedicated Bearer A2 corresponding to Filter A2. When the user data to be transmitted matches Filter D1, UE_A 10 may transmit the user data using Default Bearer 1 corresponding to Filter D1.

  In the example of the UE-initiated PDN connection disconnection procedure (WLAN access network), the case has been described where only the communication path by WLAN access associated with the multi-access PDN connection is disconnected.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[2.4.2. Explanation of network-led PDN connection disconnection procedure (WLAN access network)]
Next, an example of a PDN connection disconnection procedure for disconnecting a communication path by WLAN access associated with a multi-access PDN connection led by a network will be described with reference to FIG.

  The PCRF_A 60 and the PGW_A 30 may detect the deterioration of the radio wave state of the WLAN access system or the instability of the connectivity, and start the PDN connection disconnection procedure. Moreover, PCRF_A60 and PGW_A30 may start the PDN connection disconnection procedure at an arbitrary timing.

  First, the PCRF_A 60 transmits a message for requesting an IP-CAN update procedure to the PGW_A 30 in order to start the PDN connection disconnection procedure (S2502). The message for requesting the IP-CAN update procedure may include at least first identification information and / or third identification information.

  Here, the first identification information may be NBIFO Indication indicating that the PDN connection is a multi-access PDN connection. The first identification information may be Mode Indication indicating the NBIFO operation mode of the multi-access PDN connection. UE_A10 may include UE-Initiated mode or Network-Initiated mode in the first identification information.

  The third identification information may be NBIOM Capability indicating that the network supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the third identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the third identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The PGW_A 30 receives the message for requesting the IP-CAN update procedure transmitted by the PCRF_A 60. The PGW_A 30 receives the message for requesting the IP-CAN update procedure and / or ePDG_A65 based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. A session deletion request is transmitted to (S2504).

  The PGW_A 30 receives at least the message for requesting the IP-CAN update procedure and / or at least based on the first identification information and / or the third identification information included in the message for requesting the IP-CAN update procedure. The first identification information and / or the third identification information may be included in the session deletion request and transmitted.

  Note that the method of starting the PDN connection disconnection procedure is not limited to the method of starting PCRF_A 60 in the IP-CAN session update procedure described so far, and PGW_A 30 may start. At this time, the PGW_A 30 may generate the first identification information and / or the third identification information, and transmit it by including it in the session deletion request.

  The ePDG_A 65 receives the session deletion request transmitted by the PGW_A 30. The ePDG_A 65 transmits an INFORMATIONAL request (INFORMATIONAL request) to the UE_A 10 based on the reception of the session deletion request and / or the first identification information and / or the third identification information included in the session deletion request (S2506).

  The ePDG_A 65 may transmit the INFORMATION request including at least the delete payload (DELETE payload) based on the reception of the session deletion request and / or the first identification information and / or the third identification information included in the session deletion request. . Further, the ePDG_A 65 may include at least the first identification information and / or the third identification information in the INFORMATION request. Further, the ePDG_A 65 may include a PDN connection ID (PDN connection ID) in the INFORMATION request.

  Here, the deletion payload may be information included to indicate that a tunnel disconnection between the UE_A 10 and the ePDG_A 65 is requested. Therefore, the ePDG_A 65 may request disconnection of the PDN connection by including the deletion payload in the INFORMATION request. Note that the INFORMATIONAL request may be an IKEv2 message.

  The PDN connection ID may be information for uniquely identifying the PDN connection established between the UE_A 10 and the PGW_A 30.

  UE_A10 receives the INFORMATIONAL request transmitted by ePDG_A65. The UE_A 10 receives the INFORMATION request and / or transmits an INFORMATION response to the ePDG_A 65 based on the first identification information and / or the third identification information included in the INFORMATION request (S2508). Note that the INFORMATION response message may be a control message indicating that the disconnection of the PDN connection is permitted. Further, the INFORMATION response message may be a response message to the INFORMATION request.

  The UE_A 10 may receive the INFORMATIONAL request and / or transmit the deleted security association list in the INFORMATIONAL response based on the first identification information and / or the third identification information included in the INFORMATION request. Further, the UE_A 10 may include at least the first identification information and / or the second identification information in the INFORMATION response. Further, UE_A 10 may include the PDN connection ID in the INFORMATION response.

  Here, the second identification information may be UE NBIOM Capability indicating that UE_A 10 supports NBIOM. NBIOM capability may be information indicating that it has a function of establishing a multi-access PDN connection.

  In this way, by transmitting the first identification information and / or the second identification information, it may be indicated that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected. In other words, the first identification information and / or the second identification information may be information indicating that only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected.

  The deleted security association list may be information including a list of security associations disconnected by ePDG_A65. Note that the INFORMATION response may be an IKEv2 message.

  UE_A10 is identified by the PDN connection ID based on the reception of the INFORMATION request and / or the transmission of the INFORMATION response and / or the first identification information and / or the third identification information and / or the PDN connection ID included in the INFORMATION request. Only the communication path by the WLAN access associated with the multi-access PDN connection may be disconnected. More specifically, the UE_A 10 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the UE_A 10 may delete the default access associated with the multi-access PDN connection. In other words, UE_A10 may delete the default access matched with the multi-access PDN connection, when all the contexts for the communication path by the WLAN access matched with the multi-access PDN connection are deleted. More specifically, when the UE_A 10 deletes all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection, the default access included in the UE context for each PDN associated with the multi-access PDN connection. May be deleted.

  Therefore, UE_A10 is identified by the PDN connection ID based on the reception of the INFORMATION request and / or the transmission of the first identification information and / or the third identification information included in the INFORMATION request and / or the PDN connection ID and / or the INFORMATION response. The default access associated with the multi-access PDN connection to be performed may be deleted.

  In this way, the UE_A 10 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  ePDG_A65 receives the INFORMATIONAL response transmitted by UE_A10. The ePDG_A 65 transmits a session deletion response to the PGW_A 30 based on the reception of the INFORMATION response and / or the first identification information and / or the second identification information included in the INFORMATION response (S2510). Note that it may be a response message to the session deletion request.

  The ePDG_A 65 includes at least the first identification information and / or the second identification information in the session deletion response based on the reception of the INFORMATION response and / or the first identification information and / or the second identification information included in the INFORMATION response. You may send it. Further, the ePDG_A 65 may include the PDN connection ID in the session deletion response.

  The PGW_A 30 receives the session deletion response transmitted by the ePDG_A 65. The PGW_A 30 transmits a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. (S2512).

  The PGW_A 30 receives at least the first identification information and / or the second identification information based on the reception of the session deletion response and / or the first identification information and / or the second identification information included in the session deletion response. It may be transmitted by being included in a message for notifying completion of the procedure.

  When the PGW_A 30 starts the PDN connection disconnection procedure instead of the PCRF_A 60, the PGW_A 30 may not transmit a message for notifying the PCRF_A 60 of the completion of the IP-CAN update procedure.

  The PGW_A 30 receives a session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or first identification information and / or second identification information and / or PDN connection included in the session deletion response Based on the ID, only the communication path by the WLAN access associated with the multi-access PDN connection identified by the PDN connection ID may be disconnected. More specifically, the PGW_A 30 may disconnect the communication path by the WLAN access by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection.

  Further, when all the communication paths by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 may delete the default access associated with the multi-access PDN connection. In other words, the PGW_A 30 may delete the default access associated with the multi-access PDN connection when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted. More specifically, when all the contexts for the communication path by the WLAN access associated with the multi-access PDN connection are deleted, the PGW_A 30 is a default included in the EPS bearer context for each PDN associated with the multi-access PDN connection. Access may be deleted.

  Accordingly, the PGW_A 30 receives the session deletion response and / or transmits a message for notifying completion of the IP-CAN update procedure and / or the first identification information and / or the second identification information included in the session deletion response and / or Based on the PDN connection ID, the default access associated with the multi-access PDN connection identified by the PDN connection ID may be deleted.

  In this way, the PGW_A 30 disconnects the communication path by the WLAN access associated with the multi-access PDN connection by deleting the context for the communication path by the WLAN access associated with the multi-access PDN connection and / or the default access. May be.

  Upon completion of the network-driven PDN connection disconnection procedure (WLAN access network), UE_A 10 and PGW_A 30 establish a multi-access PDN connection that does not have a communication path for WLAN access. The multi-access PDN connection that does not have a communication path by WLAN access may be a multi-access PDN connection that has only a communication path by 3GPP access.

  Note that there may be only one default bearer associated with a multi-access PDN connection having only a communication path by 3GPP access. Therefore, when having a multi-access PDN connection having only a communication path by 3GPP access, the UE_A 10 and the PGW_A 30 may select a default bearer without using default access, and transmit / receive user data using the selected default bearer. Good.

  After completing the network-initiated PDN connection disconnection procedure (WLAN access network), the UE_A 10 and the PGW_A 30 may transmit and receive user data based on the stored context for the communication path by 3GPP access.

  Note that the UE_A10 and PGW_A30 transmitting / receiving user data after the completion of the network-initiated PDN connection disconnection procedure (WLAN access network) is the UE-initiated PDN connection disconnection procedure (WLAN access) described in Chapter 2.4.1. Network) It may be the same as the method of transmission / reception after completion. Therefore, the description of the user data transmission / reception method is omitted here.

  In the example of the network-initiated PDN connection disconnection procedure (WLAN access network), the case where only the communication path by the WLAN access associated with the multi-access PDN connection is disconnected has been described.

  Through the above procedure, UE_10A and / or PGW_A30 delete the default access based on disconnecting one of the communication path via 3GPP access and the communication path via WLAN access established for the multi-access PDN connection. Communication can be continued. In other words, UE_10A and / or PGW_A30 can continue communication by deleting one of the default bearer associated with 3GPP access and the default bearer associated with WLAN access.

[2.4.3. Explanation of UE-led PDN connection disconnection procedure (3GPP access network)]
An example of a PDN connection disconnection procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by the UE may be the same as the procedure example described in Chapter 1.4.3. Therefore, the description is omitted here.

[2.4.4. Explanation of network-led PDN connection disconnection procedure (3GPP access network)]
An example of a PDN connection disconnection procedure for disconnecting a communication path by 3GPP access associated with a network-led multi-access PDN connection may be the same as the procedure example described in Chapter 1.4.4. Therefore, the description is omitted here.

[2.4.5. Explanation of UE-led detachment procedure (3GPP access network)]
An example of a detach procedure for disconnecting a communication path by 3GPP access associated with a multi-access PDN connection led by a UE may be the same as the procedure example described in section 1.4.5. Therefore, the description is omitted here.

[2.4.6. Explanation of network-driven detachment procedure (3GPP access network)]
An example of a detach procedure for disconnecting a communication path by 3GPP access associated with a network-led multi-access PDN connection may be the same as the procedure example described in Chapter 1.4.6. Therefore, the description is omitted here.

[3. Modified example]
The program that operates in the mobile station apparatus and the base station apparatus related to the present invention is a program (a program that causes a computer to function) that controls the CPU and the like so as to realize the functions of the above-described embodiments related to the present invention. Information handled by these devices is temporarily stored in the RAM at the time of processing, then stored in various ROMs and HDDs, read out by the CPU, and corrected and written as necessary. As a recording medium for storing the program, a semiconductor medium (for example, ROM, nonvolatile memory card, etc.), an optical recording medium (for example, DVD, MO, MD, CD, BD, etc.), a magnetic recording medium (for example, magnetic tape, Any of a flexible disk etc. may be sufficient. In addition, by executing the loaded program, not only the functions of the above-described embodiment are realized, but also based on the instructions of the program, the processing is performed in cooperation with the operating system or other application programs. The functions of the invention may be realized.

  In the case of distribution in the market, the program can be stored and distributed in a portable recording medium, or transferred to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is also included in the present invention. Moreover, you may implement | achieve part or all of the mobile station apparatus and base station apparatus in embodiment mentioned above as LSI which is typically an integrated circuit. Each functional block of the mobile station apparatus and the base station apparatus may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used. In the above-described embodiment, LTE and WLAN (for example, IEEE802.11a / b / n) are described as examples of the radio access network, but they may be connected by WiMAX instead of WLAN. The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and the design and the like within the scope not departing from the gist of the present invention are also claimed. Included in the range.

9 Communication system 10 UE_A
30 PGW_A
35 SGW_A
40 MME_A
45 eNB_A
50 HSS_A
55 AAA_A
60 PCRF_A
65 ePDG_A
70 WLAN ANa
74 TWAG_A
75 WLAN ANb
80 LTE AN_A
90 Core Network_A
100 PDN_A

Claims (20)

A terminal device,
A control unit that establishes a first default bearer to connect to the first access network, and establishes a second default bearer to connect to the second access network and establishes a multi-access PDN (Packet Data Network) connection When,
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
A storage unit for storing a default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network;
A transmission / reception unit that performs data transmission / reception using the first default bearer or the second default bearer based on the default access;
The transceiver receives an EPS bearer context deactivation request message including at least an EPS bearer ID via the first access network;
The said control part deletes the said default access, when the said EPS bearer ID is the information which identifies the said 1st default bearer or the said 2nd default bearer. The terminal device characterized by the above-mentioned. The EPS bearer context deactivation request message includes at least information indicating that the PDN connection is a multi-access PDN connection, and / or NBIOM (Network-based IP Flow Mobility) capability information. The terminal device according to claim 1. A terminal device,
A control unit that establishes a first default bearer to connect to the first access network, and establishes a second default bearer to connect to the second access network and establishes a multi-access PDN (Packet Data Network) connection When,
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
A storage unit for storing a default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network;
A transmission / reception unit that performs data transmission / reception using the first default bearer or the second default bearer based on the default access;
The transmitting / receiving unit receives an information request message or information response message including at least the PDN connection ID via the second access network,
The said control part deletes the said default access, when the said PDN connection ID is the information which identifies the said multi-access PDN connection. The terminal device characterized by the above-mentioned. The PDN connection disconnection request message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or NBIOM (Network-based IP Flow Mobility) capability information. Item 4. The terminal device according to Item 3. A terminal device,
A control unit that establishes a first default bearer to connect to the first access network, and establishes a second default bearer to connect to the second access network and establishes a multi-access PDN (Packet Data Network) connection When,
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
A storage unit for storing a default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network;
A transmission / reception unit that performs data transmission / reception using the first default bearer or the second default bearer based on the default access;
The transceiver receives a detach request message or a detach acceptance message via the first access network,
The control unit deletes the default access based on reception of the detach request message or the detach acceptance message. The detach request message or the detach acceptance message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or capability information of NBIOM (Network-based IP Flow Mobility). The terminal device according to claim 5. A PDN (Packet Data Gateway) gateway device,
A control unit that establishes a first default bearer to connect to the first access network, and establishes a second default bearer to connect to the second access network and establishes a multi-access PDN (Packet Data Network) connection When,
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
A storage unit for storing a default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network;
A transmission / reception unit that performs data transmission / reception using the first default bearer or the second default bearer based on the default access;
The transmission / reception unit receives a session deletion request message or a session deletion response message including at least a PDN connection ID,
The control unit deletes the default access when the PDN connection ID is information for identifying the multi-access PDN connection. The PDN gateway apparatus according to claim 7, wherein the session deletion request message is a control message transmitted by a gateway apparatus that connects the first access network and a core network. The PDN gateway apparatus according to claim 7, wherein the session deletion request message is a control message transmitted by a gateway apparatus that connects the second access network and a core network. The session deletion request message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or information indicating NBIOM (Network-based IP Flow Mobility) capability information. The PDN gateway device according to claim 7. A communication control method for a terminal device,
Establishing a first default bearer to connect to the first access network and establishing a second default bearer to connect to the second access network to establish a multi-access PDN (Packet Data Network) connection;
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
Based on the default access default access, which is information associated with the multi-access PDN connection and indicating the first access network or the second access network, the first default bearer or the second default Send and receive data using bearers,
Receiving an EPS bearer context deactivation request message including at least an EPS bearer ID via the first access network;
If the EPS bearer ID is information for identifying the first default bearer or the second default bearer, the default access is deleted. The EPS bearer context deactivation request message includes at least information indicating that the PDN connection is a multi-access PDN connection, and / or NBIOM (Network-based IP Flow Mobility) capability information. The communication control method for a terminal device according to claim 11. A communication control method for a terminal device,
Establishing a first default bearer to connect to the first access network and establishing a second default bearer to connect to the second access network to establish a multi-access PDN (Packet Data Network) connection;
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
Use of the first default bearer or the second default bearer based on the default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network Send and receive data,
Receiving an INFORMATIONAL request message or an INFORMATION response message including at least the PDN connection ID via the second access network;
When the PDN connection ID is information for identifying the multi-access PDN connection, the default access is deleted. The PDN connection disconnection request message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or NBIOM (Network-based IP Flow Mobility) capability information. Item 14. A communication control method for a terminal device according to Item 13. A communication control method for a terminal device,
Establishing a first default bearer to connect to the first access network and establishing a second default bearer to connect to the second access network to establish a multi-access PDN (Packet Data Network) connection;
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
Use of the first default bearer or the second default bearer based on the default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network Send and receive data,
Receiving a detach request message or a detach acceptance message via the first access network;
The communication control method for a terminal device, wherein the default access is deleted based on reception of the detach request message or the detach acceptance message. The detach request message or the detach acceptance message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or capability information of NBIOM (Network-based IP Flow Mobility). The communication control method for a terminal device according to claim 15. A communication control method for a PDN (Packet Data Gateway) gateway device,
Establishing a first default bearer to connect to the first access network and establishing a second default bearer to connect to the second access network to establish a multi-access PDN (Packet Data Network) connection;
The first access network is a 3GPP access network;
The second access network is an Untrusted Non-3GPP access network;
Use of the first default bearer or the second default bearer based on the default access which is information associated with the multi-access PDN connection and is information indicating the first access network or the second access network Send and receive data,
Receiving a session deletion request message or a session deletion response message including at least the PDN connection ID;
The communication control method for a PDN gateway apparatus, wherein the default access is deleted when the PDN connection ID is information for identifying the multi-access PDN connection. The communication control method for a PDN gateway device according to claim 17, wherein the session deletion request message is a control message transmitted by a gateway device that connects the first access network and a core network. The communication control method for a PDN gateway apparatus according to claim 17, wherein the session deletion request message is a control message transmitted by a gateway apparatus that connects the second access network and a core network. The session deletion request message includes at least information indicating that the PDN connection is a multi-access PDN connection and / or information indicating NBIOM (Network-based IP Flow Mobility) capability information. The communication control method of the PDN gateway apparatus according to claim 17.

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