WO2017078702A1

WO2017078702A1 - Method and apparatus for implementing localized routing

Info

Publication number: WO2017078702A1
Application number: PCT/US2015/059037
Authority: WO
Inventors: Devaki Chandramouli; Giorgi Gulbani; Vesa Pauli Hellgren
Original assignee: Nokia Solutions and Networks Oy
Current assignee: Nokia Solutions and Networks Oy
Priority date: 2015-11-04
Filing date: 2015-11-04
Publication date: 2017-05-11
Anticipated expiration: 2018-05-04

Abstract

A method and apparatus may include establishing a first packet data network connection with a first user equipment. The first packet data network connection is established via at least one serving gateway and via a first evolved Node B. The apparatus, the first evolved Node B, and the at least one serving gateway support localized routing. The method may also include establishing a second packet data network connection with a second user equipment. The second packet data network connection is established via the at least one serving gateway and via a second evolved Node B. The second evolved Node B supports localized routing. The method may also include comparing a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. The method may also include transmitting a request to begin localized routing based on the comparing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

Description

METHOD AND APPARATUS FOR IMPLEMENTING LOCALIZED ROUTING

BACKGROUND:

Field:

[0001] Certain embodiments of the present invention relate to implementing localized routing based on General-Packet-Radio-Service Tunneling Protocol (GTP).

Description of the Related Art:

[0002] Long-term Evolution (LTE) is a standard for wireless communication that seeks to provide improved speed and capacity for wireless communications by using new modulation/signal processing techniques. The standard was proposed by the 3^rd Generation Partnership Project (3 GPP), and is based upon previous network technologies. Since its inception, LTE has seen extensive deployment in a wide variety of contexts involving the communication of data.

SUMMARY:

[0003] According to a first embodiment, a method may include establishing, by a packet-data-network gateway, a first packet data network connection with a first user equipment. The first packet data network connection is established via at least one serving gateway and via a first evolved Node B. The packet-data-network gateway, the first evolved Node B, and the at least one serving gateway support localized routing. The method may also include establishing a second packet data network connection with a second user equipment. The second packet data network connection is established via the at least one serving gateway and via a second evolved Node B, and the second evolved Node B supports localized routing. The method may also include comparing a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing may include comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. The method may also include transmitting a request to begin localized routing based on the comparing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0004] In the method of the first embodiment, the comparing a source and a destination of the at least one packet may include comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool. The request is transmitted if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

[0005] In the method of the first embodiment, the method may also include determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway.

[0006] In the method of the first embodiment, the determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway comprises comparing serving-gateway-fully-qualified-tunnel-endpoint identifiers of the first packet data network connection and the second packet data network connection.

[0007] In the method of the first embodiment, the transmitting the request may include transmitting the request to different serving gateways if the first packet data network connection and the second packet data network connection are determined to be established via different serving gateways.

[0008] In the method of the first embodiment, the transmitting the request may include transmitting the request to the first and second evolved Node Bs if the first packet data network connection and the second packet data network connection are determined to be established via the same serving gateway. The localized routing may be configured to transmit packets between the first evolved Node B and the second evolved Node B without being transmitted via the single serving gateway. [0009] In the method of the first embodiment, the transmitting a request may include transmitting a general-packet-radio-service tunneling procedure message to the at least one serving gateway.

[0010] According to a second embodiment, an apparatus may include at least one processor. The apparatus may also include at least one memory including computer program code. The at least one memory and the computer program code may be configured, with the at least one processor, to cause the apparatus at least to establish a first packet data network connection with a first user equipment. The first packet data network connection is established via at least one serving gateway and via a first evolved Node B. The apparatus, the first evolved Node B, and the at least one serving gateway support localized routing. The apparatus may also be caused to establish a second packet data network connection with a second user equipment. The second packet data network connection is established via the at least one serving gateway and via a second evolved Node B. The second evolved Node B supports localized routing. The apparatus may also be caused to compare a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing may include comparing the source and the destination with a plurality of addresses corresponding to the apparatus. The apparatus may also be caused to transmit a request to begin localized routing based on the comparing. The localized routing may be configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the apparatus. The apparatus may include a packet-data-network gateway.

[0011] In the apparatus of the second embodiment, the comparing a source and a destination of the at least one packet may include comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool. The request may be transmitted if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

[0012] In the apparatus of the second embodiment, the apparatus may be further caused to determine whether the first packet data network connection and the second packet data network connection are established via a single serving gateway. [0013] In the apparatus of the second embodiment, the determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway may include comparing serving-gateway-fully-qualified-tunnel-endpoint identifiers of the first packet data network connection and the second packet data network connection.

[0014] In the apparatus of the second embodiment, the transmitting the request may include transmitting the request to different serving gateways if the first packet data network connection and the second packet data network connection are determined to be established via different serving gateways.

[0015] In the apparatus of the second embodiment, the transmitting the request may include transmitting the request to the first and second evolved Node Bs if the first packet data network connection and the second packet data network connection are determined to be established via the same serving gateway. The localized routing may be configured to transmit packets between the first evolved Node B and the second evolved Node B without being transmitted via the single serving gateway.

[0016] In the apparatus of the second embodiment, the transmitting a request may include transmitting a general-packet-radio-service tunneling procedure message to the at least one serving gateway.

[0017] According to a third embodiment, a computer program product may be embodied on a non-transitory computer readable medium. The computer program product may be configured to control a processor to perform a method according to the first embodiment.

[0018] According to a fourth embodiment, a method may include establishing, by a serving gateway, a first packet data network connection with a first user equipment. The first packet data network connection may be established via a first evolved Node B. The serving gateway and the first evolved Node B support localized routing. The method may also include establishing a second packet data network connection with a second user equipment. The second packet data network connection is established via a second evolved Node B. The second evolved Node B supports localized routing. The method may also include receiving a request, from a packet-data-network gateway, to begin localized routing based on a comparing. The request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing may include comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. The method may also include performing localized routing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0019] In the method of the fourth embodiment, the comparing may include comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool. The request may be received if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

[0020] In the method of the fourth embodiment, the receiving a request may include receiving a general-packet-radio-service tunneling procedure message from the packet-data-network gateway.

[0021] According to a fifth embodiment, an apparatus may include at least one processor. The apparatus may also include at least one memory including computer program code. The at least one memory and the computer program code may be configured, with the at least one processor, to cause the apparatus at least to establish a first packet data network connection with a first user equipment. The first packet data network connection is established via a first evolved Node B. The serving gateway and the first evolved Node B support localized routing. The apparatus may include a serving gateway. The apparatus may also be caused to establish a second packet data network connection with a second user equipment. The second packet data network connection is established via a second evolved Node B. The second evolved Node B supports localized routing. The apparatus may also be caused to receive a request, from a packet-data-network gateway, to begin localized routing based on a comparing. The request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing may include comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. The apparatus may also be caused to perform localized routing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0022] In the apparatus of the fifth embodiment, the comparing may include comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool. The request is received if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

[0023] In the apparatus of the fifth embodiment, the receiving a request may include receiving a general-packet-radio-service tunneling procedure message from the packet-data-network gateway.

[0024] According to a sixth embodiment, a computer program product may be embodied on a non-transitory computer readable medium. The computer program product may be configured to control a processor to perform a method according to the fourth embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS:

[0025] For proper understanding of the invention, reference should be made to the accompanying drawings, wherein:

[0026] Fig. 1 illustrates a first scenario where two UEs are communicating with each other via a same Packet Data Network (PDN) Gateway (PGW) (or a same unified gateway (uGW) in 5G) and via a same Serving Gateway (SGW).

[0027] Fig. 2 illustrates a PGW that sends GTP messages, in accordance with certain embodiments.

[0028] Fig. 3 illustrates a second scenario when two UEs are communicating with each other via the same PGW (or via the same uGW in 5G), but via different SGWs (SGW-1 and SGW-2). [0029] Fig. 4 illustrates a flowchart of a method in accordance with certain embodiments of the invention.

[0030] Fig. 5 illustrates a flowchart of a method in accordance with certain embodiments of the invention.

[0031] Fig. 6 illustrates an apparatus in accordance with certain embodiments of the invention.

[0032] Fig. 7 illustrates an apparatus in accordance with certain embodiments of the invention.

[0033] Fig. 8 illustrates an apparatus in accordance with certain embodiments of the invention.

DETAILED DESCRIPTION:

[0034] Currently, GTP User Plane (GTP-U) protocol is the prevailing protocol that is used for delivering user plane data to 3GPP packet core nodes. Packet core nodes may include network nodes such as Radio Network Controllers (RNC), evolved Node Bs (eNB), Serving GPRS Support Nodes (SGSN), Serving Gateways (SGW), Packet Data Network (PDN) Gateways (PGW), and/or Gateway GPRS Support Nodes (GGSN), for example. Generic Routing Encapsulation (GRE) protocol is also used for delivering user plane data to 3 GPP packet core nodes, but GRE is generally limited to Proxy Mobile Ipv6 (ΡΜΙΡνβ) based S2a, S2b, and S5 interface deployments.

[0035] Future mobile networks (such as 5G mobile networks, for example) may require methods for routing which are more flexible than the current approaches. In order to achieve these methods for routing, enhancements to GTP-U may be necessary.

[0036] Currently, if two user equipment (UEs) are communicating with each other, while having established Packet Data Network (PDN) connections to the same Serving Gateway (SGW), the user plane data still flows via the same PGW (or possibly via two different PGWs, if the PDNs terminate to two different PGWs). Having the user plane data flow via the same PGW may be necessary for consistent charging, but this data flow is generally not a desirable configuration, from a routing standpoint. [0037] Proxy Mobile IPv6 (ΡΜΙΡνβ) network elements (such as Mobile Access Gateways (MAG) and Local Mobility Anchors (LMA), for example) may detect that two Mobile Nodes (MNs) are communicating via a same MAG, or via a same LMA. If the two MNs are communicating via a same MAG or a same LMA, then localized routing may be initiated. For example, if the same MAG serves both MNs, the network instructs the MAG to locally route the user plane data. For example, the network may instruct the MAG to locally route the user plane data such that the data will not go through the LMA(s) anymore. After a while, if the network detects that the MNs have moved away from each other, the network may instruct the MAG to resume ordinary routing via the LMA(s).

[0038] Certain embodiments introduce local routing functionality for Evolved Packet Core (EPC). Two embodiments are proposed based on the existing EPC architecture, and these embodiments may also be applied to future networks. For example, the two embodiments may be applicable to 5G mobile networks as well.

[0039] A first embodiment may be directed to modifications to both GPRS Tunneling Protocol Version 2 (GTPv2) and/or GPRS Tunneling Protocol Version 1 - User Plane (GTPvl-U). A second embodiment may be directed to a modification to GTPvl-U only.

[0040] The following scenarios describe the functionality provided by certain embodiments, for Evolved Packet Core (EPC) networks. Certain embodiments may provide similar functionality for 5G networks.

[0041] Certain embodiments may address certain scenarios, as described in more detail below. In 3GPP terms, the below descriptions may be considered to be stage 2 descriptions.

[0042] Fig. 1 illustrates a first scenario where two UEs are communicating with each other via a same PGW (or a same unified gateway (uGW) in 5G) and via a same SGW. Referring to Fig. 1 , the solid-line arrows may represent control plane tunnels (such as, for example, GTPv2 tunnels), while the dashed-line arrows may represent user plane tunnels (such as, for example, GTPvl-U tunnels). [0043] Referring to Fig. 1, first, UE-1 establishes a PDN connection to a PGW. According to certain embodiments, PGW and SGW may exchange information regarding localized routing capability via control/user plane signaling (as described in more detail below).

[0044] Second, with certain embodiments, SGW and eNB-1 may also exchange information regarding localized routing capability via control/user plane signalling (as described in more detail below). In the below steps, it is assumed that PGW, SGW, and eNB-1 all support localized routing functionality.

[0045] Third, UE-2 also establishes a PDN connection to a PGW via eNB-2 and the SGW. Fourth, SGW and eNB-2 also exchange information regarding localized routing capability. It may also be assumed that eNB-2 supports the localized routing functionality. Fifth, UE-1 and UE-2 may establish a communication channel via application layer signalling (not shown in Fig. 1).

[0046] When UE-1 sends user plane Internet Protocol (IP) packets to UE-2 via the PGW, the PGW generally removes outer headers (if the packets are sent in accordance with Internet-Protocol / User-Datagram-Protocol / GPRS-Tunnelling-Protocol (IP/UDP/GTP)) of the IP packets before sending the IP packets to UE-2.

[0047] Sixth, although not shown in Fig. 1 , before sending an IP packet to UE-2, the PGW compares the source and the destination IP addresses of the IP packet (these source and destination IP addresses may be set by the UE) against IP addresses of an IP address pool (of the PGW). The IP address pool may contain the IP addresses allocated to the UE for the PDN connections served by the PGW. Therefore, two IP addresses belonging to UE addressing are compared. The source and destination IP addresses of the IP packet are generally included in the IP header of the IP packet. This comparison of the source and destination IP addresses may be readily performed because PGW may have already received/inspected the original packet with the headers (see step 5), such that, for example, there maybe no need for additional packet inspection. In the event that there is no need for additional packet inspection, PGW may more easily detect that both of the source and destination IP addresses belong to the same IP address pool. The PGW may provide an indication that both of the IP addresses belong to the same IP address pool.

[0048] Seventh, the PGW sends the IP packets to UE-2. With certain embodiments, the PGW compares the IP addresses of SGW Fully Qualified Tunnel Endpoint Identifiers (F-TEIDs) for each PDN connection. The SGW F-TEID of each PDN connection contains the IP address of the SGW that serves the PDN connection, and if the IP addresses of SGW F-TEIDs of both PDN connections are both the same, then the same SGW is serving both PDN connections. In this scenario, the PDN connections correspond to the same SGW.

[0049] Eighth, as illustrated by Fig. 2, with certain embodiments, PGW sends GTP messages of a new type (where the new GTP messages may include Localized Routing Requests, control plane messages, and/or user plane messages, for example). Fig. 2 illustrates a PGW that sends GTP messages, in accordance with certain embodiments. The PGW may send the GTP messages to the SGW, which instructs the SGW to start localized routing, as described in more detail below.

[0050] Ninth, the SGW may acknowledge the start of the localized routing, or the SGW may reject the request, as described in more detail below. Tenth, with certain embodiments, the SGW may filter for data packets transmitted from UE-1 to UE-2, based on the inner IP headers, and the SGW may start routing the packets directly to eNB-2. Therefore, the SGW may stop routing data to the PGW. Eleventh, although not shown in Fig. 2, similar steps may be used for routing user plane traffic from UE-2 to UE-1.

[0051] Twelfth, with certain embodiments, the SGW may filter the traffic for a given data stream to identify if the data is exchanged via the same eNB, or via two eNBs. If the data flows via two eNBs, the SGW will identify whether the IP subnets (for which the eNB-1 and eNB-2 belong to) are connected or not. If the IP subnets are connected, the different eNBs can communicate directly with each other, and the SGW will send GTP messages of a new type (where the new GTP message may include a Localized Routing Request, control plane request, and/or user plane request) to each eNB. The message may instruct the eNB to start localized routing (as described in more detail below). Each eNB may then either acknowledge that it is ready to start localized routing, or each eNB may reject the request for starting localized routing. In either case, the SGW may not send any further request messages to eNBs.

[0052] Thirteenth, with certain embodiments, if an eNB is ready to start localized routing, the eNB will send GTP messages of a new type (e.g., a Localized Routing Request, a control plane request, and/or a user plane request) to the other eNB. The other eNB may either accept the request, reject the request, and/or ignore the request.

[0053] Fourteenth, with certain embodiments, if an eNB receives acceptance of the request to start localized routing from the other eNB, the requesting eNB may start forwarding the user plane data directly to the other eNB.

[0054] With certain embodiments, a second scenario may be directed to a scenario where communication occurs via the same PGW, but via different SGWs. Fig. 3 illustrates the scenario when two UEs are communicating with each other via the same PGW (or via the same uGW in 5G), but via different SGWs (SGW-1 and SGW-2).

[0055] The second scenario may include certain steps that are different from the steps of the first scenario of Figs. 1 and 2 (where the first scenario corresponds to the scenario where UEs communicate with each other via a same SGW and a same PGW). First, UE-1 may establish a PDN connection to a PGW via SGW-1. During the setup of the PDN connection, PGW and SGW-1 may exchange information regarding localized routing capability via control/user plane signalling.

[0056] Second, SGW-1 and eNB-1 may also exchange information regarding localized routing capability via the control/user plane signalling. In the following steps, it may be assumed that PGW, SGW-1 , and eNB-1 all support localized routing. Third, UE-2 also establishes a PDN connection to the PGW via eNB-2 and SGW-2.

[0057] Fourth, SGW-2 and eNB-2 also exchange information regarding localized routing capability, and it may be assumed also that eNB-2 and SGW-2 support localized routing.

[0058] Fifth, UE-1 and UE-2 establish a communication channel via application layer signalling (not shown in Fig. 3). UE-1 sends user plane IP packets to UE-2 via the PGW. The PGW may replace outer headers (if the packets are transmitted in accordance with IP/UDP/GTP) before sending the IP packets to UE-2.

[0059] Sixth, before sending the IP packets to UE-2, the PGW may compare the source and the destination IP addresses (included within the IP headers of the packets) against a set of addresses corresponding to the PGW, and the PGW may detect that both the source and the destination IP addresses belong to a same IP address pool (of the PGW). The PGW may provide an indication that the source and the destination IP addresses belong to the same IP address pool (not shown in Fig. 3).

[0060] Seventh, the PGW may send the IP packets to UE-2. The PGW may compare the IP addresses of SGW F-TEIDs for each of the two PDN connections, and the PGW may determine that the two PDN connections are different (the determination is not shown in Fig. 3). Specifically, the PGW may determine that the PDN connections have differing SGWs (SGW-1 and SGW-2), for example. Eighth, PGW sends, for example, Localized Routing Request GTP messages to the SGW-1 and SGW-2. These messages may instruct the SGWs to start localized routing. SGWs may acknowledge the start of the localized routing, or may reject the request to start localized routing.

[0061] Ninth, SGW-1 may filter the packets transmitted from UE-1 to UE-2, filtering based upon the inner IP headers, for example. SGW-1 may start routing the packets directly to SGW-2. Therefore, the SGW-1 may stop routing the packets to the PGW.

[0062] Tenth, similar steps may be used for transmitting user plane traffic from UE-2 to UE-1 (such steps are not shown in Fig. 3).

[0063] Certain embodiments may be utilized with a third scenario, which is directed to communication via different PGWs. If UE-1 and UE-2 establish PDN connection to different PGWs, then the following three use cases should be considered. With a first use case, the same SGW may serve both PDN connections to PGW-1 and PGW-2 in the same Public Land Mobile Network (PLMN). PGWs may need to exchange messages to confirm the capability for localized routing, and also to detect that a same SGW is used (by looking into the exchanged SGW F-TEID). The exchanged messages may include, for example, Localized Routing Request/Response GTP. [0064] With a second case, different SGWs (such as SGW-1 and SGW-2) may serve the PDN connections to PGW-1 and PGW-2 in the same PLMN. PGWs may need to exchange messages to confirm that each PGW has the capability for localized routing, and also to detect whether the same SGW is used (by referring to the exchanged SGW F-TEID). The exchanged messages may include Localized Routing Request/Response GTP messages, for example.

[0065] With regard to protocol details of certain embodiments, a protocol-level description of certain embodiments of the invention is included below. In 3GPP terms, the following description may be considered to be a stage 3 description.

[0066] With regard to new messages, as described above, certain embodiments may utilize new signalling messages that may comprise either new control plane messages (such as GTPv2, for example) and/or new user plane messages (such as GTPvl-U, for example).

[0067] The new GTP request messages (which may include a Localized Routing Request, for example) may contain the following information elements.

[0068] The request message may include bearer contexts. There may be two instances of bearer contexts, which identify the PDN connections for which the localized routing is defined. The request message may include an EPS Bearer Identity (EBI) that identifies a default bearer of the PDN connection. The request message may also include a Traffic Flow Template (TFT) that defines traffic filters for the PDN connection. If the uplink (UL) packet of the PDN connection (the source PDN connection) that is defined by EBI matches the TFT, the packet will be forwarded to the PDN connection (the target PDN connection) of the other Bearer Context Information Element (IE), and, after that, the packet will be handled as the downlink (DL) packet of the target PDN connection. The packet filters in the TFT generally contain IPv4/IPv6 remote addresses, which define a single IP address and the IP address matches the UE IP address of the other PDN connection.

[0069] The request message may also use F-TEID for localized routing between two nodes. The IE (which includes F-TEID information) may be optional, and the IE may be used only in those cases where the localized routing requires forwarding the packet to another node of the same type (e.g., SGW to SGW, or eNB to eNB). For example, a localized routing may be created between two eNBs (as shown by Figure 2). The IE may contain the F-TEID of the remote node. If the localized routing is defined within a single node, the F-TEIDs of the original bearers may be used.

[0070] A response message (such as a Localized Routing Response, for example) may contain the following information elements. The response message may include a Sender F-TEID. The response message may also include a Cause. The Sender F-TEID is used when localized routing in the other receiver of the response message needs to forward the packet to the sender of the response message. The Cause is used to indicate whether a request was accepted or rejected.

[0071] A Localized routing tunnel may remain active until a Localized Routing Request is sent. The Localized Routing Response may be used to acknowledge the request. An Update Localized Routing Request/Response may be used in case the Traffic Flow Template (TFT) of the localized routing tunnel is to be updated.

[0072] Fig. 4 illustrates a flowchart of a method in accordance with certain embodiments of the invention. The method illustrated in Fig. 4 includes, at 410, establishing, by a packet-data-network gateway, a first packet data network connection with a first user equipment. The first packet data network connection is established via at least one serving gateway and via a first evolved Node B. The packet-data-network gateway, the first evolved Node B, and the at least one serving gateway support localized routing. The method may also include, at 420, establishing a second packet data network connection with a second user equipment. The second packet data network connection is established via the at least one serving gateway and via a second evolved Node B. The second evolved Node B may support localized routing. The method may also include, at 430, comparing a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. The method may also include, at 440, transmitting a request to begin localized routing based on the comparing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0073] Fig. 5 illustrates a flowchart of a method in accordance with certain embodiments of the invention. The method illustrated in Fig. 5 includes, at 510, establishing, by a serving gateway, a first packet data network connection with a first user equipment. The first packet data network connection is established via a first evolved Node B. The serving gateway and the first evolved Node B support localized routing. The method may also include, at 520, establishing a second packet data network connection with a second user equipment. The second packet data network connection is established via a second evolved Node B. The second evolved Node B supports localized routing. The method may also include, at 530, receiving a request, from a packet-data-network gateway, to begin localized routing based on a comparing. The request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing may include comparing the source and the destination with a plurality of addresses that correspond to the packet-data-network gateway. The method may also include, at 540, performing localized routing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0074] Fig. 6 illustrates an apparatus in accordance with certain embodiments of the invention. In one embodiment, the apparatus can be a SGW or PGW, for example. In another embodiment, the apparatus may be an evolved Node B or a UE, for example. The apparatus may be configured to perform, at least, the methods described in Fig. 4 and/or Fig. 5. Apparatus 10 can include a processor 22 for processing information and executing instructions or operations. Processor 22 can be any type of general or specific purpose processor. While a single processor 22 is shown in Fig. 6, multiple processors can be utilized according to other embodiments. Processor 22 can also include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), and processors based on a multi-core processor architecture, as examples. [0075] Apparatus 10 can further include a memory 14, coupled to processor 22, for storing information and instructions that can be executed by processor 22. Memory 14 can be one or more memories and of any type suitable to the local application environment, and can be implemented using any suitable volatile or nonvolatile data storage technology such as a semiconductor-based memory device, a magnetic memory device and system, an optical memory device and system, fixed memory, and removable memory. For example, memory 14 include any combination of random access memory (RAM), read only memory (ROM), static storage such as a magnetic or optical disk, or any other type of non-transitory machine or computer readable media. The instructions stored in memory 14 can include program instructions or computer program code that, when executed by processor 22, enable the apparatus 10 to perform tasks as described herein.

[0076] Apparatus 10 can also include one or more antennas (not shown) for transmitting and receiving signals and/or data to and from apparatus 10. Apparatus 10 can further include a transceiver 28 that modulates information on to a carrier waveform for transmission by the antenna(s) and demodulates information received via the antenna(s) for further processing by other elements of apparatus 10. In other embodiments, transceiver 28 can be capable of transmitting and receiving signals or data directly.

[0077] Processor 22 can perform functions associated with the operation of apparatus 10 including, without limitation, precoding of antenna gain/phase parameters, encoding and decoding of individual bits forming a communication message, formatting of information, and overall control of the apparatus 10, including processes related to management of communication resources.

[0078] In an embodiment, memory 14 can store software modules that provide functionality when executed by processor 22. The modules can include an operating system 15 that provides operating system functionality for apparatus 10. The memory can also store one or more functional modules 18, such as an application or program, to provide additional functionality for apparatus 10. The components of apparatus 10 can be implemented in hardware, or as any suitable combination of hardware and software. [0079] Fig. 7 illustrates an apparatus in accordance with certain embodiments of the invention. Apparatus 700 can be a network node such as a PGW, for example. Apparatus 700 can include a first establishing unit 710 that establishes a first packet data network connection with a first user equipment. The first packet data network connection is established via at least one serving gateway and via a first evolved Node B. The packet-data-network gateway, the first evolved Node B, and the at least one serving gateway support localized routing. Apparatus 700 may also include a second establishing unit 720 that establishes a second packet data network connection with a second user equipment. The second packet data network connection is established via the at least one serving gateway and via a second evolved Node B. The second evolved Node B may support localized routing. Apparatus 700 may also include a comparing unit 730 that compares a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway. Apparatus 700 may also include a transmitting unit 740 that transmits a request to begin localized routing based on the comparing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0080] Fig. 8 illustrates an apparatus in accordance with certain embodiments of the invention. Apparatus 800 can be a network node that is configured to perform as an SGW, for example. Apparatus 800 can include a first establishing unit 810 that establishes a first packet data network connection with a first user equipment. The first packet data network connection is established via a first evolved Node B. Apparatus 800 and the first evolved Node B support localized routing. Apparatus 800 may also include an establishing unit 820 that establishes a second packet data network connection with a second user equipment. The second packet data network connection is established via a second evolved Node B, and the second evolved Node B supports localized routing. Apparatus 800 may also include a receiving unit 830 that receives a request, from a packet-data-network gateway, to begin localized routing based on a comparing. The request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment. The comparing comprises comparing the source and destination with a plurality of addresses that correspond to the packet-data-network gateway. Apparatus 800 may also include a performing unit 840 that performs localized routing. The localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

[0081] The described features, advantages, and characteristics of the invention can be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages can be recognized in certain embodiments that may not be present in all embodiments of the invention. One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the invention.

Claims

WE CLAIM:

1. A method, comprising:

establishing, by a packet-data-network gateway, a first packet data network connection with a first user equipment, wherein the first packet data network connection is established via at least one serving gateway and via a first evolved Node B, and the packet-data-network gateway, the first evolved Node B, and the at least one serving gateway support localized routing;

establishing a second packet data network connection with a second user equipment, wherein the second packet data network connection is established via the at least one serving gateway and via a second evolved Node B, and the second evolved Node B supports localized routing;

comparing a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment, wherein the comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway; and

transmitting a request to begin localized routing based on the comparing, wherein the localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

2. The method according to claim 1, wherein the comparing a source and a destination of the at least one packet comprises comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool, and the request is transmitted if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

3. The method according to claim 1 or 2, further comprising determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway.

4. The method according to claim 3, wherein the determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway comprises comparing serving-gateway-fully-qualified-tunnel-endpoint identifiers of the first packet data network connection and the second packet data network connection.

5. The method according to claim 3 or 4, wherein the transmitting the request comprises transmitting the request to different serving gateways if the first packet data network connection and the second packet data network connection are determined to be established via different serving gateways.

6. The method according to claim 3 or 4, wherein the transmitting the request comprises transmitting the request to the first and second evolved Node Bs if the first packet data network connection and the second packet data network connection are determined to be established via the same serving gateway, and the localized routing is configured to transmit packets between the first evolved Node B and the second evolved Node B without being transmitted via the single serving gateway.

7. The method according to any of claims 1-5, wherein the transmitting a request comprises transmitting a general-packet-radio-service tunneling procedure message to the at least one serving gateway.

8. An apparatus, comprising:

at least one processor; and

at least one memory including computer program code,

the at least one memory and the computer program code configured, with the at least one processor, to cause the apparatus at least to

establish a first packet data network connection with a first user equipment, wherein the first packet data network connection is established via at least one serving gateway and via a first evolved Node B, and the apparatus, the first evolved Node B, and the at least one serving gateway support localized routing;

establish a second packet data network connection with a second user equipment, wherein the second packet data network connection is established via the at least one serving gateway and via a second evolved Node B, and the second evolved Node B supports localized routing;

compare a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment, wherein the comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the apparatus; and

transmit a request to begin localized routing based on the comparing, wherein the localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the apparatus, and the apparatus comprises a packet-data-network gateway.

9. The apparatus according to claim 8, wherein the comparing a source and a destination of the at least one packet comprises comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool, and the request is transmitted if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

10. The apparatus according to claim 8 or 9, wherein the apparatus is further caused to determine whether the first packet data network connection and the second packet data network connection are established via a single serving gateway.

11. The apparatus according to claim 10, wherein the determining whether the first packet data network connection and the second packet data network connection are established via a single serving gateway comprises comparing serving-gateway-fully-qualified-tunnel-endpoint identifiers of the first packet data network connection and the second packet data network connection.

12. The apparatus according to claim 10 or 11, wherein the transmitting the request comprises transmitting the request to different serving gateways if the first packet data network connection and the second packet data network connection are determined to be established via different serving gateways.

13. The apparatus according to claim 10 or 11, wherein the transmitting the request comprises transmitting the request to the first and second evolved Node Bs if the first packet data network connection and the second packet data network connection are determined to be established via the same serving gateway, and the localized routing is configured to transmit packets between the first evolved Node B and the second evolved Node B without being transmitted via the single serving gateway.

14. The apparatus according to any of claims 8-12, wherein the transmitting a request comprises transmitting a general-packet-radio-service tunneling procedure message to the at least one serving gateway.

15. A computer program product, embodied on a non-transitory computer readable medium, the computer program product configured to control a processor to perform a method according to any of claims 1-7.

16. A method, comprising:

establishing, by a serving gateway, a first packet data network connection with a first user equipment, wherein the first packet data network connection is established via a first evolved Node B, and the serving gateway and the first evolved Node B support localized routing;

establishing a second packet data network connection with a second user equipment, wherein the second packet data network connection is established via a second evolved Node B, and the second evolved Node B supports localized routing; receiving a request, from a packet-data-network gateway, to begin localized routing based on a comparing, wherein the request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment, and the comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway; and performing localized routing, wherein the localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

17. The method according to claim 16, wherein the comparing comprises comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool, and the request is received if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

18. The method according to claim 16 or 17, wherein the receiving a request comprises receiving a general-packet-radio-service tunneling procedure message from the packet-data-network gateway.

19. An apparatus, comprising:

at least one processor; and

at least one memory including computer program code,

establish a first packet data network connection with a first user equipment, wherein the first packet data network connection is established via a first evolved Node B, and the serving gateway and the first evolved Node B support localized routing, and the apparatus comprises a serving gateway;

establish a second packet data network connection with a second user equipment, wherein the second packet data network connection is established via a second evolved Node B, and the second evolved Node B supports localized routing; receive a request, from a packet-data-network gateway, to begin localized routing based on a comparing, wherein the request is based on a comparing of a source and a destination of at least one packet that is transmitted between the first user equipment and the second user equipment, and the comparing comprises comparing the source and the destination with a plurality of addresses corresponding to the packet-data-network gateway; and

perform localized routing, wherein the localized routing is configured to transmit packets between the first user equipment and the second user equipment without being transmitted via the packet-data-network gateway.

20. The apparatus according to claim 19, wherein the comparing comprises comparing a source internet protocol address of the at least one packet and a destination internet protocol address of the at least one packet with addresses of an internet protocol address pool, and the request is received if the source internet protocol address and the destination internet protocol address belong to the internet protocol address pool.

21. The apparatus according to claim 19 or 20, wherein the receiving a request comprises receiving a general-packet-radio-service tunneling procedure message from the packet-data-network gateway.

22. A computer program product, embodied on a non-transitory computer readable medium, the computer program product configured to control a processor to perform a method according to any of claims 16-18.