WO2012106984A1

WO2012106984A1 - Method and system for accessing mobile core network through trustworthy fixed network

Info

Publication number: WO2012106984A1
Application number: PCT/CN2012/070492
Authority: WO
Inventors: 刘国燕; 毕以峰; 宗在峰; 周晓云; 霍玉臻
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-02-10
Filing date: 2012-01-17
Publication date: 2012-08-16
Also published as: CN102740401A

Abstract

Disclosed are a method and system for accessing a mobile core network through a trustworthy fixed network. The technical solution is as follows: after mobile UE accesses an RG, the RG sends a message to a bandwidth gateway (BNG)/bandwidth remote access server (BRAS), triggers message interaction between the fixed network and the mobile core network, and asks the mobile core network to allocate an IP address to the UE; after the RG obtains the IP address allocated by the mobile core network to the mobile UE and carries out a corresponding IP address mapping relationship processing, it provides the IP address to the mobile UE; and the mobile UE accesses a service through the mobile network or directly through the fixed network using the IP address provided by the RG. The present invention enhances the message between the UE and the fixed network element, and ensures that the UE can access the mobile core network through the trustworthy WLAN network and access the service provided by the mobile network.

Description

Method and system for accessing mobile core network through trusted fixed network

The present invention relates to the field of mobile communications, and in particular, to a method and system for a mobile terminal to access a mobile core network through a trusted fixed network to access a service provided by a mobile operator or a fixed network operator. Background technique

The Evolved Packet System (EPS) of the 3rd Generation Partnership Project (3GPP) is evolved by Evolved Universal Terrestrial Radio Access Network (E-UTRAN), mobile management. A component (Mobility Management Entity, MME), a Serving Gateway (S-GW), a Packet Data Network Gateway (P-GW), and a Home Subscriber Server (HSS).

The EPS supports interworking with non-3GPP systems, wherein interworking with non-3GPP systems is implemented through an S2a/b/c interface, and the P-GW acts as an anchor between 3GPP and non-3GPP systems. In the system architecture diagram of EPS, non-3GPP system access is divided into untrusted non-3GPP access and trusted non-3GPP access; wherein, untrusted non-3GPP access requires evolved packet data gateway (Evolved Packet Data Gateway) , ePDG) is connected to the P-GW, the interface between the ePDG and the P-GW is S2b; the trusted non-3GPP access can be directly connected to the P-GW through the S2a interface, and the S2a interface uses the PMIP protocol for information exchange; in addition, the S2c interface Provides user plane-related control and mobility support between User Equipment (UE) and P-GW. The supported mobility management protocol is dual-stack mobile IPv6 (Moblie IPv6 Support for Dual Stack Hosts and Routers, DSMIPv6), which can be used for untrusted non-3GPP and trusted non-3GPP access. The WLAN network can be used as a trusted non-3GPP access EPS. Because the WLAN network itself has two networking modes, including a routing gateway or a residential gateway (RG), RG is a bridge mode, and RG is a routing mode. Therefore, when WLAN and EPS are intercommunicated, different considerations are needed. Technical requirements for networking mode and EPS interworking.

When the RG is in the bridging mode, when the UE accesses the fixed network service, the fixed network allocates the local IP and can trigger the Broadband Network Gateway I Broadband Remote Access Server (BNG/BRAS). The mobile core network initiates Proxy Mobile IP (PMIP) tunnel establishment. This only requires BNG/BRAS to support the PMIP protocol, and can return the address assigned by the mobile network to the terminal to the terminal.

When the RG is in the routing mode (as shown in Figure 1 and Figure 2), when the UE accesses the fixed network service, the specific steps of the process are as follows: First, the BNG/BRAS allocates the local IP to the RG (for example: the client device address, Customer Premises Equipment) IP, abbreviated as CPE IP), and then RG is used as a dynamic host configuration protocol server (DHCP Server) to assign an IP address (generally a private address;) to the UE through a DHCP message. After the IP address, the fixed network service can be accessed through the BNG/BRAS; however, if the UE accesses the mobile core network through the WLAN network, the existing message mechanism of the routing mode (as shown in FIG. 2) cannot trigger the BNG/BRAS to pass. The S2a interface sends a PMIP message to the mobile core network to obtain an IP address assigned to the terminal from the mobile core network, and uses the IP address to access the service provided by the mobile operator. Summary of the invention

In view of this, the main object of the present invention is to provide a method and system for accessing a mobile core network through a trusted fixed network, which is used to solve the problem that the existing message mechanism UE cannot be triggered when the fixed network is used as a trusted non-3GPP network. The core network assigns an IP address to it, which causes the UE to have no access to the technical problems of the services provided by the mobile operator.

In order to achieve the above object, the technical solution of the present invention is achieved as follows: A method for a UE to access a mobile core network through a trusted fixed network, the method is applied to a mobile user terminal (UE) accessing a mobile core network by trusting a fixed network, and the home gateway (RG) in the fixed network is in a routing mode Scenario, after the mobile UE accesses the RG, the RG sends a message to the broadband gateway (BNG)/broadband remote access server (BRAS), triggers message interaction between the fixed network and the mobile core network, and requests the mobile core network as the UE. Assign an IP address;

After obtaining the IP address allocated by the mobile core network for the mobile UE, and performing corresponding IP address mapping processing, the RG provides the IP address to the mobile UE;

The mobile UE uses the IP address provided by the RG to access the service through the mobile network or directly through the fixed network.

Further, before the “RG sends a message to the BNG/BRAS”, the method further includes: performing a Point-to-Point Protocol Link Control Protocol (PPP LCP) negotiation between the mobile UE and the RG, and completing a point-to-point protocol extended identity verification protocol ( PPP EAP) authentication process, and implementation of peer-to-peer IP Control Protocol (PPP IPCP) negotiation.

Further, if the mobile UE supports the coexistence of two IP addresses, before the PPP LCP negotiation between the mobile UE and the RG, the method further includes: the mobile UE sending a dynamic host configuration protocol (DHCP) message to the RG, where After the mobile UE completes the DHCP negotiation with the RG, the RG allocates an address to the mobile UE. If the mobile UE supports only one IP address, the mobile UE directly performs PPP LCP negotiation with the RG. The user identification information determines whether the mobile UE is currently accessing.

Further, the RG is to trigger a message interaction between the fixed network and the mobile core network, and the message sent to the BNG/BRAS is a DHCP message or a Proxy Mobile IP (PMIP) message, where the DHCP message or the PMIP message includes an international Mobile Subscriber Identity (IMSI) and Access Point Name (APN) information.

After the BNG/BRAS receives the DHCP message or PMIP message sent by the RG, it sends The PMIP message is sent to a packet data network gateway (P-GW) to complete a process related to the mobile network; the process related to the mobile network includes: PMIP tunnel establishment and IP address allocation, IP-CAN session establishment, and P-GW identity Update process.

Further, the RG obtains an IP address allocated by the mobile core network for the mobile UE by using a DHCP message or a PMIP message sent by the BNG.

Further, the network allocates two IP addresses or one IP address to the mobile UE; the two IP addresses include an IP address allocated by the fixed network for the UE and an IP address allocated by the mobile network to the UE; The mapping between the IP address assigned to the UE by the fixed network and the IP address assigned to it by the mobile network.

The mobile UE uses the IP address provided by the RG to perform corresponding encapsulation processing on the data packet, including:

In the case that the mobile UE saves two IP addresses or stores an IP address assigned by the mobile core network, and needs to access the service through the mobile network, the mobile UE encapsulates the source address into a packet for the mobile core network. Assigned IP address;

When the mobile UE saves an IP address assigned by the fixed network, the mobile UE encapsulates the source address of the packet into an IP address assigned by the fixed network.

In the process of the mobile UE accessing the service through the mobile network, the RG performs address mapping processing on the data packet according to the local IP address mapping relationship, including:

When the mobile UE saves two IP addresses or saves an IP address assigned by the mobile core network, and needs to access the service through the mobile network, the RG is responsible for packet forwarding;

When the mobile UE saves an IP address assigned by the fixed network, the RG changes the IP address assigned by the fixed network to the mobile UE to the mobile core network as the mobile according to the IP address mapping relationship. The IP address assigned by the UE to access the service through the mobile network, or to perform corresponding policy routing based on the service characteristics.

Based on the above method, the present invention also proposes to access the mobile core network through a trusted fixed network. Network system, the system includes:

An address obtaining module, configured to perform message interaction between the UE, the RG, the BNG/BRAS, and the mobile core network, to obtain an IP address allocated by the mobile core network to the mobile UE; in the module, the RG sends a message to the BNG/BRAS, triggering Message interaction between the fixed network and the mobile core network, requesting and acquiring the mobile core network to allocate an IP address to the mobile UE;

The address processing module is configured to: after the RG obtains the IP address assigned by the mobile core network to the UE, perform corresponding IP address mapping relationship processing, and provide the IP address to the UE;

The service access module is used by the UE to use the IP address provided by the RG to access the service through the mobile network or directly through the fixed network.

Further, the system further includes:

a PPP negotiation module, configured to perform a point-to-point protocol link control protocol (PPP LCP) negotiation between the mobile UE and the RG before the RG sends a message to the BNG/BRAS, and complete a point-to-point protocol extended identity insurance agreement (PPP EAP) The authentication process, as well as the implementation of peer-to-peer IP Control Protocol (PPP IPCP) negotiation.

The invention enhances the message between the UE and the fixed network element (including: RG, BNG), ensures that the UE can access the mobile core network through the trusted WLAN network, and access the service provided by the mobile network. DRAWINGS

1 is an architectural diagram of a UE accessing a mobile core network through a trusted non-3GPP network; FIG. 2 is a flowchart of a UE accessing a mobile core network through a trusted non-3GPP network; FIG. 3 is a trusted UE of the present invention. FIG. 4 is a scheme for a UE to access a mobile core network through a trusted non-3GPP network. FIG. 5 is a scheme for a UE of the present invention to access a mobile core network through a trusted non-3GPP network. FIG. 6 is a fourth scheme of the UE of the present invention accessing a mobile core network through a trusted non-3GPP network. detailed description

The present invention will be further described in detail below with reference to the accompanying drawings.

Example 1

This procedure is that RG is in the routing mode and WLAN is used as a trusted non-3GPP network. The mobile terminal UE accesses the mobile core network through the S2a interface. The fixed network and the mobile network respectively allocate an IP address to the UE, and store two IP addresses in the UE. The DHCP protocol is used between RG and BNG/BRAS to solve the problem that the RG and BNG/BRAS cannot forward the IP address assigned by the mobile network to the terminal UE. As shown in Figure 3, it includes:

Step 301: A point-to-point protocol (PPP) negotiation and authentication process is performed between the RG and the BNG/BRAS. In the PPP negotiation process, the BNG/BRAS allocates a local IP address, that is, a CPE IP, to the RG.

Step 302: The DHCP negotiation process is performed between the UE and the RG. In the DHCP negotiation process, the RG allocates an IP address to the UE, which is generally a private network IP, which is called IP2.

Step 303: If the UE is a mobile terminal, that is, a mobile UE, perform PPP Link Control Protocol (PPP Link Control Protocol, PPP LCP) negotiation with the RG.

Step 304: After receiving the PPP LCP request message of the UE, the RG, as the authenticator, sends an authentication request message to the UE to complete the UE to the 3GPP authentication server (for example, Authorization Authentication and Accounting). Server, AAA Server) EAP authentication process. In the EAP authentication process, the RG can identify the UE as a mobile terminal user. Step 305: After receiving the EAP authentication request message, the BNG/BRAS initiates establishment of a fixed network policy session with the Broadband Policy Control Function (BPCF), and the BPCF triggers the policy and charging rule function. (Policy and Charging Rules Function, PCRF) establishment of a policy session; By establishing a good policy session, the management strategy resources can be uniformly coordinated between the mobile network and the fixed network.

Step 306: After completing the EAP authentication, the UE initiates a PPP IP Control Protocol (IPCP) request message to the RG.

Step 307: After receiving the PPP IPCP request message, the RG constructs a DHCP discover message locally according to the judgment of step 304, if the UE is a mobile terminal user, the message includes: an access point name (APN) Information required by mobile networks such as the International Mobile Subscriber Identification Number (IMSI).

Step 308: After receiving the DHCP discovery message, the BNG/BRAS sends a Proxy Binding Update (PBU) message to the P-GW, where the message includes: ΑΡΝ, IMSI, etc., to request IP from the P-GW. Address allocation.

Step 309: After receiving the PBU message, the P-GW establishes an IP-Connectivity Access Network (IP-CAN) session with the PCRF.

Step 310: If the P-GW changes, the P-GW identifier is updated to the HSS.

Step 311: After receiving the PBU message, the P-GW sends a Proxy Binding Acknowledgement (PBA) message to the BNG/BRAS, where the IP address assigned to the terminal is called IP1.

Steps 312-313: After receiving the PBA message, the BNG/BRAS obtains the IP1 from the message, fills in the DHCP providing message, and returns to the RG. After receiving the DHCP-provided message, the RG obtains the IP1 and sends a DHCP request/DHCP response message to the BNG/BRAS that responds with the response. Confirm the assigned IP1.

Step 314: After receiving the DHCP response message, the RG sends a PPP IPCP failure response message to the UE, where the message carries the IP1 address to the UE.

Optionally, after receiving the DHCP response message, the RG may obtain an IP address locally, which is called IP3, and locally store the mapping relationship between IP1 and IP3. Then, the RP sends a PPP IPCP negative response message to the UE, where the message carries The IP3 address is given to the UE.

Step 314a: After receiving the PPP IPCP negative acknowledgment message, the UE will respond to the RG through the PPP IPCP request/PPP IPCP to confirm the assigned IP1 or IP3 address to the RG (specifically, the IP carried in the PPP IPCP negative response message is subject to ).

Step 315: If there is a policy that needs to be updated, the PCRF will trigger it and BPCF,

A policy update operation will be performed between BNG/BRAS and BPCF.

Step 316: The UE may perform data transmission according to the offloading policy obtained from the network side/local configuration, and the specific operations are as follows:

A) offloading data (see step 316a): When the UE determines that the service data needs to be offloaded, the UE will fill the IP source address of the service 4 as IP2, and the destination address is the real destination address of the message; When the RG is sent to the RG, the RG will change the IP address of the packet to the CPE IP and send it to the BNG/BRAS. After receiving the packet, the BNG/BRAS sends the packet to the real IP network. destination.

B) Data accessed from the mobile network (see step 316b): When the UE determines that the service data needs to be accessed through the mobile network, the UE will fill the IP source address of the service with IP1 and the destination address is 4 The true destination address; RG, BNG/BRAS, and mobile network devices can route data to and from it.

Optionally, if the UE obtains the IP3, the UE fills the IP address of the service packet with the IP3 address, and the destination address is the real destination address of the packet. After receiving the packet, the RG saves the packet according to the local Mapping the IP1 and IP3, modifying the IP address of the packet to IP1, and then routing Forward.

The above description only describes the encapsulation mechanism of the uplink packet, and the encapsulation mechanism of the downlink packet performs the destination IP address mapping operation in the packet header, which is not specifically described herein.

In addition, in addition to the PMIP protocol, the GPRS Tunneling Protocol (GTP) can be used between the BNG/BRAS and the P-GW. If the GTP protocol is used, the PBU message is changed to create a session request message, PB. The A message corresponds to the creation of a session response message.

Description:

1) There is no order between steps 309-311.

2) Step 315 can occur at any time after step 305. Example 2

This procedure is that RG is in the routing mode and WLAN is used as a trusted non-3GPP network. The mobile terminal UE accesses the mobile core network through the S2a interface. The fixed network and the mobile network respectively allocate an IP address to the UE, and store two IP addresses in the UE. The difference from Embodiment 1 is that the PMIP protocol is adopted between RG and BNG/BRAS to solve the problem that the IP address assigned by the mobile network to the terminal UE cannot be forwarded between RG and BNG/BRAS. As shown in FIG. 4, the method includes the following steps: Step 401: PPP negotiation and authentication process between the RG and the BNG/BRAS. In the PPP negotiation process, the BNG/BRAS allocates a local IP address, that is, a CPE IP, to the RG.

Step 402: The DHCP negotiation process is performed between the UE and the RG. In the DHCP negotiation process, the RG allocates an IP address to the UE, which is generally a private network IP, which is called IP2.

Step 403: If the UE is a mobile terminal, the UE performs PPP LCP negotiation with the RG.

Step 404: After receiving the PPP LCP request message of the UE, the RG, as the authenticator, initiates a PPP EAP authentication request message to the UE. In the EAP authentication process, the RG can identify the UE as a mobile terminal user and complete the UE to the 3GPP authentication server. (Example: AAA Server) EAP certification process.

Step 405: After receiving the EAP authentication request message, the BNG/BRAS initiates establishment of a fixed network policy session with the BPCF, and the BPCF further triggers establishment of a policy session with the PCRF; The management strategy resources can be unified and coordinated between the network and the fixed network.

Step 406: After completing the EAP authentication, the UE initiates a PPP IPCP request message to the RG. Step 407: After receiving the PPP IPCP request message, the RG determines, according to the judgment of step 404, if the UE is a mobile terminal user, locally constructs a PBU message, where the message includes: information required by the mobile network such as APN and IMSI.

After receiving the PBU message, the BNG/BRAS forwards the PBU message to the P-GW, and the message includes: APN, IMSI, and the like to request IP address allocation from the P-GW.

Step 408: After receiving the PBU message, the P-GW will establish an IP-CAN session with the PCRF, and will reply to the BNG/BRAS with a PBA message carrying the IP address assigned to the terminal, which is called IP1.

Step 409: If the P-GW changes, the P-GW identifier is updated to the HSS.

Step 410: The BNG/BRAS forwards the PBA message to the RG.

Step 411: After receiving the PB A message, the RG sends a PPP IPCP negative response message to the UE, where the message carries the IP1 address to the UE.

Optionally, after receiving the PBA message, the RG may locally allocate an IP address, which is called IP3, and locally store the mapping relationship between IP1 and IP3; and then send a PPP IPCP negative response message to the UE, where the message carries the IP3. Address to the UE.

Step 411a: After receiving the PPP IPCP negative acknowledgment message, the UE will respond to the RG through the PPP IPCP request/PPP IPCP to confirm the assigned IP1 or IP3 address to the RG (specifically, the IP carried in the PPP IPCP negative response message is subject to ). Step 412: If there is a policy that needs to be updated, the PCRF will trigger a policy update operation with BPCF, BNG/BRAS and BPCF.

Step 413: The UE may perform data transmission according to the offloading policy obtained from the network side/local configuration, and the specific operations are as follows:

A) The offloading data (see step 413a): When the UE determines that the service data needs to be offloaded, the UE will fill the IP source address of the service packet with IP2, and the destination address is the real destination address of the packet; When the RG is reached, the RG will change the IP address of the packet to the CPE IP and send it to the BNG/BRAS. After receiving the packet, the BNG/BRAS sends the packet to the real destination through the external IP network. .

B) Data accessed from the mobile network (see step 413b): When the UE determines that the service data needs to be accessed through the mobile network, the UE fills the IP source address of the service packet with IP1, and the destination address is 4 The real destination address; RG, BNG/BRAS, and mobile network devices can forward and forward data.

Optionally, if the UE obtains the IP3, the UE fills the IP address of the service packet with the IP3 address, and the destination address is the real destination address of the packet. After receiving the packet, the RG saves the packet according to the local In the mapping table of IP1 and IP3, modify the IP source address of the packet to IP1, and then perform route forwarding.

In addition, the GTP protocol can be used between the BNG/BRAS and the P-GW in addition to the PMIP protocol. If the GTP protocol is used, the PBU message is changed to create a session request message, and the PBA message is changed to create a session response message.

Description:

1) There is no order between steps 408-410.

2) Step 412 can occur at any time after step 405. Example 3

The process is similar to the first embodiment. The main difference is that the address obtained by the UE is an IP address, for example, the mobile network allocates it or assigns it to the fixed network. As shown in FIG. 5, the method includes: Step 501: RG and The PNG negotiation and authentication process is performed between the BNG/BRAS. During the PPP negotiation process, the BNG/BRAS allocates a local IP address, that is, a CPE IP, to the RG.

Step 502: If the UE is a mobile terminal, perform PPP LCP negotiation with the RG.

Step 503: After receiving the PPP LCP request message of the UE, the RG, as the authenticator, initiates a PPP EAP authentication request message to the UE. In the EAP authentication process, the RG can identify the UE as a mobile terminal user and complete the UE to the 3GPP authentication server. (For example: AAA Server) EAP authentication process.

Step 504: After receiving the EAP authentication request message, the BNG/BRAS initiates establishment of a fixed network policy session with the BPCF, and the BPCF further triggers establishment of a policy session with the PCRF. The management strategy resources can be unified and coordinated between the network and the fixed network.

Step 505: After completing the EAP authentication, the UE initiates a PPP IPCP request message to the RG. Step 506: After receiving the PPP IPCP request message, the RG determines, according to the determination in step 303, if the UE is a mobile terminal user, locally constructs a DHCP discovery message, where the message includes: information required by the mobile network such as APN and IMSI.

Step 507: After receiving the DHCP discovery message, the BNG/BRAS sends a PBU message to the P-GW, where the message includes: APN, IMSI, and the like to request IP address allocation from the P-GW.

Step 508: After receiving the PBU message, the P-GW establishes an IP-CAN session with the PCRF.

Step 509: If the P-GW changes, the P-GW identifier is updated to the HSS. Step 510: After receiving the PBU message, the P-GW sends a PBA message to the BNG/BRAS, where the message carries the IP address assigned to the terminal, which is called IP1.

Step 511-512: After receiving the PBA message, the BNG/BRAS obtains the IP1 from the message, fills in the DHCP provision message, and replies to the RG. After receiving the DHCP offer message, the RG obtains the IP1 and sends a DHCP request/DHCP response message with the BNG/BRAS replying to the response, confirming the assigned IP1.

After receiving the IP1 allocated by the mobile network to the terminal, the RG may use one of the following two methods to transmit the corresponding data packet.

Method 1 (steps 513a, 513a, 514, 515a):

Step 513a: After receiving the DHCP response message, the RG sends a PPP IPCP failure response message to the UE, where the message carries the IP1 address to the UE.

Step 513a, after receiving the PPP IPCP negative acknowledgement message, the UE and the RG pass the PPP IPCP request/PPP IPCP response to confirm the assigned IP1 address to the RG.

Step 514: If there is a policy that needs to be updated, the PCRF will trigger a policy update operation with BPCF, BNG/BRAS and BPCF.

Step 515a: The UE encapsulates the source address of the IP header of the sent data packet into IP1, and the destination address is the destination address of the packet. Then, the packet is forwarded by the RG, BNG/BRAS, etc., and is routed to the mobile core network for access. The business provided by the mobile operator.

Method 2 (steps 513b, 513b, 514, 515b):

Step 513b: After receiving the DHCP response message, the RG sends a PPP IPCP negative response message to the UE, where the message carries the IP2 address to the UE, and the mapping relationship between IP1 and IP2 is saved locally.

Step 513b: After receiving the PPP IPCP negative acknowledgement message, the UE and the RG pass the PPP IPCP request/PPP IPCP response to confirm the assigned IP2 address to the RG.

Step 514: If there is a policy that needs to be updated, the PCRF will trigger it and the BPCF, A policy update operation will be performed between BNG/BRAS and BPCF.

Step 515b: The UE encapsulates the source address of the IP header of the sent data packet into IP2, and the destination address is the destination address of the packet; after receiving the packet, the RG changes the source address to IP1 and sends it out; It is forwarded by devices such as BNG/BRAS and routed to the mobile core network to access services provided by mobile operators.

In addition, if the solution needs to implement service offloading and directly access services through the fixed network, the RG can perform corresponding policy routing based on specific service features (such as service quintuple information), for example: directly through fixed network access. Or access the business through a mobile network.

Description:

1) There is no order between steps 508-510.

2) Step 514 can occur at any time after step 504.

Example 4

The process is similar to the first embodiment. The main difference is that the address obtained by the UE is an IP address, for example, the mobile network allocates it or assigns it to the fixed network. As shown in FIG. 6, the method includes: Step 601: RG and The PNG negotiation and authentication process is performed between the BNG/BRAS. During the PPP negotiation process, the BNG/BRAS allocates a local IP address, that is, a CPE IP, to the RG.

Step 602: If the UE is a mobile terminal, perform PPP LCP negotiation with the RG.

Step 603: After receiving the PPP LCP request message of the UE, the RG, as the authenticator, initiates a PPP EAP authentication request message to the UE. In the EAP authentication process, the RG can identify the UE as a mobile terminal user and complete the UE to the 3GPP authentication server. (For example: AAA Server) EAP authentication process.

Step 604: After receiving the EAP authentication request message, the BNG/BRAS initiates and BPCF. After the establishment of the fixed network policy session, the BPCF in turn triggers the establishment of a policy session with the PCRF; by establishing a good policy session, the management strategy resource can be uniformly coordinated between the mobile network and the fixed network.

Step 605: After completing the EAP authentication, the UE initiates a PPP IPCP request message to the RG. Step 606: After receiving the PPP IPCP request message, the RG determines, according to the determination in step 403, if the UE is a mobile terminal user, locally constructs a PBU message, where the message includes: information required by the mobile network such as APN and IMSI.

Step 607: After receiving the PBU message, the P-GW establishes an IP-CAN session with the PCRF.

Step 608: If the P-GW changes, the P-GW identifier is updated to the HSS.

Step 609: After receiving the PBU message, the P-GW replies to the BNG/BRAS with the PBA message, and the message carries the IP address assigned to the terminal, which is called IP1. The BNG/BRAS forwards the PBA message to the RG.

After receiving the IP1 assigned by the mobile network to the terminal, the RG may use one of the following two methods to encapsulate different data packets.

Method 1 (steps 610a, 610a, 611, 612a):

Step 610a: After receiving the DHCP response message, the RG sends a PPP IPCP failure response message to the UE, where the message carries the IP1 address to the UE.

Step 610a,: After receiving the PPP IPCP negative acknowledgement message, the UE and the RG acknowledge the assigned IP1 address with the PG through the PPP IPCP request/PPP IPCP response.

Step 611: If there is a policy that needs to be updated, the PCRF will trigger a policy update operation with BPCF, BNG/BRAS and BPCF. Step 612a: The UE encapsulates the source address of the IP header of the sent data packet into IP1, and the destination address is the destination address of the packet. Then, the packet is forwarded by the RG, BNG/BRAS, etc., and is routed to the mobile core network for access. The business provided by the mobile operator.

Method 2 (steps 610b, 610b \ 611, 612b):

Step 610b: After receiving the DHCP response message, the RG sends a PPP IPCP negative response message to the UE, where the message carries the IP2 address to the UE, and the mapping relationship between IP1 and IP2 is saved locally.

Step 610b: After receiving the PPP IPCP negative acknowledgement message, the UE and the RG respond with a PPP IPCP request/PPP IPCP to confirm the assigned IP2 address to the RG.

Step 611: If there is a policy that needs to be updated, the PCRF will trigger it and BPCF,

A policy update operation will be performed between BNG/BRAS and BPCF.

Step 612b: The UE encapsulates the source address of the sent data packet as IP2, and the destination address is the destination address of the packet. After receiving the packet, the RG changes the source address to IP1 and sends it out; It is forwarded by devices such as BNG/BRAS and routed to the mobile core network to access services provided by mobile operators.

In addition, if the solution needs to implement service offloading and directly access services through the fixed network, the RG can perform corresponding policy routing based on specific service features (such as service quintuple information), for example: directly through fixed network access. Or access the business through a mobile network. The above description only describes the encapsulation mechanism of the uplink packet, and the encapsulation mechanism of the downlink packet performs the mapping operation on the destination IP in the packet header, which is not specifically described herein.

Description:

1) There is no order between steps 607-609. 2) Step 611 can occur at any time after step 604, embodiment 5

Based on the foregoing method embodiments, the present invention provides a system for accessing a mobile core network through a trusted fixed network based on the foregoing method embodiments, the system comprising:

Further, the system further includes: a PPP negotiation module, configured to perform PPP LCP negotiation between the mobile UE and the RG, complete the PPP EAP authentication process, and perform PPP IPCP negotiation before the RG sends the message to the BNG/BRAS .

The system is implemented based on the foregoing method embodiments. Therefore, each module included in the system is configured to implement a corresponding step process in the foregoing method embodiments. Further, the system embodiment of the present invention may be further The function completed by each step process corresponding to each method embodiment is completed by adding a new module, so as to save space, no further details are provided here.

Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. Perform the steps shown or described, or separate them into individual integrated circuit modules, or multiple of them Blocks or steps are made in a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Industrial applicability

The invention enhances the message between the UE and the fixed network element to ensure that the UE can access the mobile core network through the trusted WLAN network and access the service provided by the mobile network.

Claims

Claim

A method for accessing a mobile core network through a trusted fixed network, the method being applied to a scenario in which a mobile user terminal UE accesses a mobile core network by trusting a fixed network, and the home gateway RG in the fixed network is in a routing mode. The method includes:

After the mobile UE accesses the RG, the RG sends a message to the broadband gateway BNG/broadband remote access server BRAS, triggers message interaction between the fixed network and the mobile core network, and requests the mobile core network to allocate an IP address for the UE;

The method according to claim 1, wherein before the RG sends a message to the BNG/BRAS, the method further includes:

The mobile UE and the RG perform a point-to-point protocol link control protocol PPP LCP negotiation, complete the point-to-point protocol extended identity verification protocol PPP EAP authentication process, and perform peer-to-peer IP control protocol PPP IPCP negotiation.

3. The method according to claim 1, wherein, if the mobile UE supports the coexistence of two IP addresses, before the PPP LCP negotiation between the mobile UE and the RG, the method further includes: the mobile UE sending to the RG a dynamic host configuration protocol DHCP message, after the mobile UE completes the DHCP negotiation with the RG, the RG allocates an address to the mobile UE;

If the mobile UE supports only one IP address, the mobile UE directly performs PPP LCP negotiation with the RG.

4. The method according to claim 1, wherein the RG determines whether the mobile UE is currently accessing according to the user identification information carried in the extended identity verification protocol (EAP) authentication message.

5. The method according to claim 1, wherein the RG is to trigger a message interaction between the fixed network and the mobile core network, and the message sent to the BNG/BRAS is a DHCP message or a proxy mobile IP, ie, a PMIP message. The DHCP message or PMIP message includes an International Mobile Subscriber Identity (IMSI) and an Access Point Name (APN) information.

6. The method according to claim 5, wherein, after receiving the DHCP message or the PMIP message sent by the RG, the BNG/BRAS sends a PMIP message to the packet data network gateway P-GW to complete the mobile network-related The process related to the mobile network includes: PMIP tunnel establishment and IP address allocation, IP-CAN session establishment, and P-GW identity update process.

The method according to claim 1, wherein the RG obtains an IP address allocated by the mobile core network for the mobile UE by using a DHCP message or a PMIP message sent by the BNG.

8. The method according to claim 1, wherein the network allocates two IP addresses or one IP address to the mobile UE; the two IP addresses include an IP address allocated by the fixed network for the UE and the mobile network allocates the UE IP address;

The IP address mapping relationship is a mapping relationship between an IP address allocated by the fixed network for the UE and an IP address allocated by the mobile network.

The method according to claim 8, wherein the mobile UE performs corresponding encapsulation processing on the data packet by using an IP address provided by the RG;

The method according to claim 8, wherein, in the process that the mobile UE needs to access the service through the mobile network, the RG performs address mapping processing on the data packet according to the local IP address mapping relationship: When the mobile UE saves two IP addresses or saves an IP address assigned by the mobile core network, and needs to access the service through the mobile network, the RG is responsible for packet forwarding;

11. A system for accessing a mobile core network through a trusted fixed network, the system comprising: an address acquisition module, configured to perform message interaction between the UE, the RG, the BNG/BRAS, and the mobile core network to obtain a mobile core The IP address assigned by the network to the mobile UE; in this module, the RG sends a message to the BNG/BRAS, triggers a message interaction between the fixed network and the mobile core network, requests and acquires the mobile core network to allocate an IP address for the mobile UE;

12. The system of claim 11 further comprising:

a PPP negotiation module, configured to perform a point-to-point protocol link control protocol PPP LCP negotiation between the mobile UE and the RG before the RG sends a message to the BNG/BRAS, and complete a peer-to-peer protocol extended identity verification protocol PPP EAP authentication process, and execute Point-to-point IP Control Protocol PPP IPCP negotiation.