WO2010124486A1

WO2010124486A1 - Method for establishing chained connection, serving gateway and packet data network gateway

Info

Publication number: WO2010124486A1
Application number: PCT/CN2009/073646
Authority: WO
Inventors: 朱春晖; 宗在峰
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-04-28
Filing date: 2009-08-31
Publication date: 2010-11-04
Also published as: CN101730074A; CN101730074B

Abstract

The invention discloses a method for establishing a chained connection, a serving gateway (S-GW) and a packet data network gateway (P-GW). The method for establishing a chained connection includes: S-GW receives the route advertisement which is sent by P-GW through the established tunnel of general packet radio service (GPRS) tunnel protocol - user plane (GTP-U), analyses and acquires the source link local address in the route advertisement; S-GW sends the proxy binding acknowledge (PBA) message carrying the source link local address to the trusted non third generation partnership project (3GPP) access gateway or evolved packet data gateway (ePDG), so that the trusted non 3GPP access gateway or ePDG performs the local link communication with the user equipment (UE) by using the source link local address on the local link between the trusted non 3GPP access gateway or ePDG and UE. The invention can reduce the requirement of P-GW and S-GW interfaces, and can reduce the cost and the implementation complexity at the same time.

Description

The present invention relates to the field of mobile communications technologies, and in particular, to a chain connection establishing method, a service gateway, and a packet data network gateway. BACKGROUND Currently, the standardization working group of the 3rd Generation Partnership Project (3GPP) is working to study the core network system of the next generation evolution as an evolved packet core network (Evolved Packet Core, called EPC). ), the purpose is to provide users with higher transmission rates and shorter transmission delays. The EPC system supports access to non-3GPP (non-3GPP) radio access networks. 1 is a schematic diagram of a non-3GPP cartridge called a VPLMN) accessing a home public land mobile network (Home PLMN, called a HPLMN). As shown in FIG. 1, the network elements included include: a packet data network gateway (Packet Data Network Gateway) , the cylinder is called PG W ), and is responsible for the gateway function of the user equipment (User Equipment, called UE) accessing the PDN (Packet Data Network); the Home Subscriber Server (the Home Subscriber Server, the tube is called HSS) ), located in the user's home network, used to permanently store user subscription data and security data. In order to support the non-3GPP access network to access the EPC, the system further includes an authentication and authorization accounting server (Authentication, Authorization and Accounting, referred to as AAA Server) and an authentication 4 authorized accounting agent (AAA Proxy). The non-3GPP access network is not an access technology standardized by the 3GPP, and the non-3GPP access network includes: a wireless office i or a network (Wireless Local Area Network), and a global interoperability access ( Worldwide Interoperability) For Microwave Access, called WIMAX), Code Division Multiple Access (CDMA), fixed broadband access. Specifically, the non-3GPP access network can be classified into the following two types: a trusted non-3GPP access network, a trust relationship between the 3GPP network and the non-3GPP access system, and a non-3GPP The access system can access the P-GW directly through S2a. Untrusted non-3GPP Access, there is no trust relationship between the 3GPP network and the non-3GPP access network, and the non-3GPP access system must first access the evolved packet data of the 3GPP network. The Evolved Packet Data Gateway (ePoG) is connected to the P-GW through the interface S2b between the ePDG and the P-GW (S2b is the interface between the ePDG and the P-GW). In this case, a secure tunnel is established between the UE and the ePDG, so that data transmission security between the UE and the 3GPP network can be ensured. The chained connection method refers to a connection mode in which the UE roams through non-3GPP Access, and then connects to the PLM of the HPLMN through a monthly service gateway (Serving Gateway, called S-GW) in the VPLMN. Specifically, FIG. 2 is a flowchart of a chain connection manner. As shown in FIG. 2, the method mainly includes the following steps: Step 201: The AAA Proxy decides to use a chain connection mode when the user accesses the authentication and the 4 吏 right, when the AAA Proxy After determining the connection mode, the AAA Proxy selects the S-GW in the VPLMN and the P-GW in the HPLMN, and sends the selected S-GW and P-GW addresses to the trusted non-3 GPP during the authentication process. Incoming or ePDG, the trusted non 3 GPP access network or ePDG saves the above address. Step 202: The trusted non-3 GPP access network or the ePDG has a Mobile Access Gateway (MAG) function, and sends a proxy binding update message (Proxy Binding Update, called a PBU) to the S-GW. The reasonable binding update message includes the address of the P-GW; Steps 203, 204: After receiving the message, the S-GW establishes a GPRS tunnel protocol (GPRS Tunnel Protocol, GTP) tunnel with the P-GW. a connection, including a tunnel of a user plane (GTP-U) and a control plane (GTP-C); Step 205: After the GTP tunnel connection between the S-GW and the P-GW is established, the S-GW sends a proxy binding The confirmation message (Proxy Binding Acknowledge, called PBA) is sent to the MAG, and the establishment of the proxy mobile IP version 6 (Proxy Mobile IPv6, called ΡΜΙΡνό) tunnel between the MAG and the S-GW is completed; Step 206: The MAG needs the UE The configuration information informs the UE. In the PMIPv6 protocol, in order to prevent the UE from colliding with the link local address of the MAG, the Local Mobility Anchor (LMA) is assigned an Interface ID (UE) for the UE. The interface identifier generates a link local address. The MAG uses the link-local address assigned by the LMA. The UE interface identifier and the MAG link local address are sent by the LMA to the MAG in a Proxy Binding Acknowledgement Message (PBA), and the UE interface identifier is sent by the MAG to the UE. The link-local address refers to an address used for communication between nodes on the local link, and cannot be used on a link other than the local. In the above process, the link is between the UE and the P-GW (between the UE and the P-GW) Only GTP tunnels, when there is no PMIPv6 tunnel) or the link between the UE and MAG (ΡΜΙΡνό). The user address is an IPv6 global address, which can be globally unique or unique to the site, that is, it can be used for global communication or intra-site communication. The site refers to the carrier network. In the GTP protocol, the P-GW allocates an interface identifier to the UE in order to prevent the link local address conflict with the UE, and sends the UE identifier to the UE when the initial network access procedure is completed, and the UE uses the interface identifier generation chain. The local address of the P-GW is used by the P-GW to notify the UE of the IPv6 address prefix assigned by the router advertisement. The source address of the route advertisement is the link-local address of the P-GW. Since the link-local address of the P-GW and the interface label of the UE are only generated by the P-GW allocation, it can be ensured that the link-local address of the P-GW and the UE does not collide. In the prior art, when a chain connection is used, as shown in FIG. 2, the P-GW sends its link local address to the S-GW in the GTP-C message in step 204, and the S-GW links the chain. The road address is sent to the MAG in the PBA (which may be a trusted non-3GPP access gateway or ePDG), and the MAG uses the above link local address on the local link with the UE. Since the method needs to extend the GTP-C message in step 204, an interface supporting the GTP-C message is required between the S-GW and the P-GW. Therefore, the existing interface needs to be extended, thereby improving the S-GW and the P. The -GW interface requirements increase cost and implementation complexity. SUMMARY OF THE INVENTION In view of this, the present invention provides an improved chain connection establishment solution for solving the problems of increasing cost and realizing complexity in the prior art due to the need to present an interface. According to an aspect of the present invention, a chain connection establishing method is provided. The chain connection establishing method according to the present invention is used for the UE to connect to the PLM of the HPLMN through the trusted non-3GPP access network or the evolved packet data gateway ePDG while roaming, and then through the S-GW of the visited public land mobile network. . In the case that the authentication 4 authorized charging agent determines to use the chain connection to access the service of the UE to the HPLMN, the chain connection establishing method of the present invention includes: the S-GW receives the P-GW sent through the established GTP-U tunnel. Route advertisements, parse and get the way By the source link local address of the advertisement; the S-GW carries the source link local address in the proxy binding acknowledgement message and sends it to the trusted non-3GPP access gateway or ePDG to make the trusted non-3GPP access gateway or ePDG Local link communication with the UE is performed using the source link local address on the local link with the UE. According to another aspect of the present invention, a service gateway is also provided. The service gateway according to the present invention includes: a receiving module, a parsing module, and a transmitting module. The receiving module is configured to receive a data packet from a packet data network gateway, where the data packet includes a route advertisement, and a parsing module, configured to parse a route advertisement in the data packet received by the receiving module, to obtain a source of the route advertisement a link-local address; a sending module, configured to carry the foregoing source link local address as a trusted non-3GPP access network or a link-local address of the ePDG in a proxy binding acknowledgement message, and send the message to the trusted non-3GPP access gateway Or ePDG. According to still another aspect of the present invention, a packet data network gateway is provided. A packet data network gateway according to the present invention includes: a receiving module, an establishing module, and a transmitting module. The receiving module is configured to receive a default load request sent by the monthly gateway or receive a routing request from the S-GW, and establish a module, configured to establish a GTP user plane tunnel and a GTP control plane from the packet data network gateway to the serving gateway. a sending module, configured to periodically send a route advertisement through a GTP user plane tunnel or send a route advertisement according to the received route request, and establish a default load response by using a GTP control plane tunnel. With the above at least one solution of the present invention, after receiving the establishment of the default bearer request, the P-GW does not need to send a GTC-C message to the S-GW, but sends a route advertisement to the S-GW, and the S-GW can analyze the The source link local address of the route advertisement acquires the link-local address on the local link between the MAG (including the trusted non-3GPP access network or the ePDG) and the UE, and does not need to be extended between the P-GW and the S-GW. The interface reduces the requirements for the interface of the P-GW and the S-GW, reducing the cost and implementation complexity. Other features and advantages of the invention will be set forth in the description which follows, and The objectives and other advantages of the invention will be realized and attained by the <RTI The drawings are intended to provide a further understanding of the invention, and are intended to be a part of the description of the invention. In the accompanying drawings: FIG. 1 is a structural diagram of receiving an EPC through a non-3GPP access network by using a chain connection when a user roams in the related art; FIG. 2 is a flowchart of using a chain connection manner in the related art; FIG. 4 is a flowchart of a specific implementation of a method for establishing a chain connection according to an embodiment of the present invention; FIG. 5 is a schematic structural diagram of a service gateway according to an embodiment of the present invention; A schematic structural diagram of a serving gateway according to a preferred embodiment of the present invention; FIG. 7 is a schematic structural diagram of a packet data network gateway according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention are directed to the prior art. When the chain connection mode is adopted, the link local address needs to be sent to the S-GW through the GTP-C message, thereby causing the S-GW and the P-GW. In the embodiment of the present invention, after receiving the default bearer request sent by the S-GW, the P-GW sends the GTP-U through the established GTP-U. The route advertisement, the S-GW receives the route advertisement, parses and obtains the source link local address of the route advertisement, and then the S-GW sends the source link local address to the trusted non-3GPP access in the proxy binding acknowledgement message. The gateway or ePDG, the trusted non-3GPP access gateway or ePDG, communicates the UE with the source link local address as its own link-local address. The embodiments in the present application and the features in the embodiments may be combined with each other without conflict. The preferred embodiments of the present invention are described in the following with reference to the accompanying drawings, which are intended to illustrate and illustrate the invention. According to the embodiment of the present invention, a chain connection establishment method is first provided, which is used for a UE to connect to a HPLMN P through a trusted non-3GPP access network or an ePDG while roaming, and then through a S-GW of the VPLMN. -GW. FIG. 3 is a flowchart of a method for establishing a chain connection according to an embodiment of the present invention. As shown in FIG. 3, a method for establishing a chain connection according to an embodiment of the present invention mainly includes (step S301 - step S303): Step S301: S- The GW receives the route advertisement advertised by the P-GW through the established GTP-U, and parses and obtains the source link local address of the route advertisement. Step S303: The S-GW carries the source link local address in the proxy binding confirmation. The message is sent to the trusted non-3GPP access gateway or ePDG to enable the trusted non-3GPP access gateway or ePDG to communicate with the UE using the source link local address on the local link with the UE. Details of each of the above processes are further described below. (1) Step S301 In the specific implementation process, when the UE accesses the IP service provided by the HPLMN through the trusted non-3GPP access network or the ePDG, the AAA Proxy determines whether to use the chain connection when the UE accesses the authentication and the 4 吏 right. embodiment, if the AAA Proxy decided chain connection, the AAA Proxy in the VPLMN a selected S-GW and P-GW in the HPLMN, and the authentication process ^ S-GW and P-GW address which selects ¹ Transmitted to the trusted non-3GPP access network or ePDG, the trusted non-3GPP access network or ePDG saves the above address, and since the trusted non-3GPP access network or ePDG has MAG function, the trusted non-3GPP access network Or the ePDG sends a proxy binding update message to the selected S-GW, where the proxy binding update message carries the selected address of the P-GW, and after receiving the proxy binding update message, the S-GW sends the message to the selected S-GW. The P-GW sends a default load request.

After receiving the establishment of the default bearer request, the P-GW establishes a GTP tunnel (including GTP-C and GTP-U) from the P-GW to the S-GW. After establishing the downlink GTP tunnel, the P-GW Sending a route advertisement to the S-GW in the established GTP-U tunnel, and replying to the S-GW in the GTP-C tunnel to establish a default bearer response. In the specific implementation process, after the GTP-C and the GTP-U tunnel are established, sending the foregoing route advertisement to the S-GW includes but is not limited to the following two methods: The first type: After the P-GW establishes the GTP tunnel, the P-GW periodically sends a route advertisement to the S-GW. The second type: after receiving the route request (Router Solicitation) sent by the S-GW, the P-GW sends the route request to the S. - GW sends the above route advertisement. The two methods are described separately below. In the method, after receiving the default bearer request from the S-GW, the P-GW periodically sends a route to the S-GW through the established downlink GTP tunnel, and the periodic route advertisement and the foregoing The sending of the default load response is not in order of time. After receiving the route advertisement, the S-GW may receive the following two situations according to the sequence of the default bearer response and the periodic route advertisement. The first case may be: The S-GW receives the P- The GW establishes a default bearer response, and then waits for the periodic route advertisement sent by the P-GW. After receiving the periodic route advertisement, it parses and acquires the source link local address in the periodic route advertisement. In the second case, The S-GW first receives the periodic route advertisement, and the S-GW parses and obtains the source link local address in the periodic route advertisement, and waits for the reception to establish a default bearer response. In the method, after the P-GW establishes the downlink GTP tunnel, the P-GW sends a default bearer response to the S-GW through the GTP-C, and the default bearer response carries the interface identifier of the UE, and the S-GW is According to the interface identifier, the source link address is generated, and the routing request is sent to the P-GW according to the source link address. After receiving the routing request, the P-GW passes the established GTP-U tunnel to the S- The GW sends the above route advertisement. In this method, if the S-GW does not receive the route advertisement sent by the P-GW within a preset time period after sending the foregoing routing request, the S-GW may send the routing request to the P-GW again, P- After receiving the routing request, the GW sends the routing request to the S-GW through the established GTP-U tunnel again, so that the unnecessary route advertisement caused by the P-GW periodically sending the route advertisement can be reduced. In order to avoid the impact of the route advertisement on the UE, and because the MAG is the access router of the UE, responsible for the communication of the local link between the UE and the network, configuring the IP address and other parameters of the UE, the S-GW does not need to send a route advertisement message. It is sent to the MAG. Therefore, after receiving the route advertisement, the S-GW may have the following two optimization processing methods after receiving the route advertisement: The first method corresponds to the first method, S - The GW intercepts the received route advertisement, and after obtaining the source link local address, discards the route advertisement data packet, and does not send it to the MAG, and the S-GW can continue to detect the P-GW passing the GTP-U tunnel. The route advertisement is sent, and the source link local address of the route advertisement is no longer obtained, and the data packet advertised by the route is discarded. Otherwise, after the S-GW obtains the source link local address, the P-GW periodicity is no longer detected. The route advertisement sent. In the second mode, corresponding to the foregoing second method, the S-GW intercepts the received route advertisement, and after obtaining the source link local address, discards the data packet of the route advertisement, and does not send the route to the P-GW. The request is such that the P-GW also no longer sends route advertisements to the S-GW.

(2) Step S303: After obtaining the source link local address of the route advertisement sent by the P-GW, the S-GW sends the source link local address in the proxy binding acknowledgement message to the S-GW. Trusted non-3GPP access gateway or ePDG (ie MAG). The trusted non-3GPP access gateway or ePDG (ie, MAG) uses the above-mentioned source link local address as its own link-local address on the local link with the UE after receiving the above-mentioned proxy binding acknowledgement message. Local link communication with the UE. To further understand the above-mentioned chain connection establishment method provided by the embodiment of the present invention, the following describes the specific implementation process of the chain connection establishment method provided by the embodiment of the present invention by sending a route advertisement as an example. FIG. 4 is a flowchart of a specific implementation of a method for establishing a chain connection according to an embodiment of the present invention. As shown in FIG. 4, the method for establishing a chain connection according to an embodiment of the present invention may be implemented by the following steps: Step 401, UE In the trusted non-3GPP access network or ePDG, when the UE is authenticated and 4 is authorized, the AAA Proxy decides to use the chain connection, and the AAA Proxy selects the S-GW in the VPLMN and the P-GW in the HPLMN, and in the authentication process. Send the selected S-GW and P-GW address to the trusted non-3GPP Access or ePDG, trusted non 3 GPP Access or ePDG Saving the above address; Step 402, the trusted non 3 GPP Access or ePDG (as the MAG specified in the PMIPv6 ten protocol) sends a proxy binding update message (ie, PBU) to the S-GW, where the proxy is bound to the update message. An address carrying the P-GW and an indication of using the GTP between the S-GW and the P-GW; Step 403: After receiving the proxy binding update message sent by the trusted Non 3GPP Access or the ePDG, the S-GW sends the P-GW to the P - The GW sends a default bearer request to be established; Step 404: The P-GW replies to the S-GW to establish a default bearer response in the GTP-C tunnel, and the P-GW sends a periodic route advertisement in the established downlink GTP-U tunnel, the route The notification is sent periodically, for example, every 10 seconds. Step 405: The S-GW obtains the default bearer response and the periodic routing advertisement according to the sequence of the above, and there are two processing situations: The first case, S- The GW first receives the periodic bearer response, and then waits for the periodic route advertisement sent by the P-GW to receive and parse the data packet in the GTP-U. After receiving and parsing the periodic route advertisement, the GW obtains the periodic route advertisement. Source link local address In the second case, the S-GW receives the periodic route advertisement. The S-GW receives and parses the data packets in the GTP-U. After receiving and parsing the periodic route advertisement, the S-GW obtains the periodic route advertisement. The source link local address in the medium, waiting to receive the default bearer response message; after the establishment of the default bearer response and the periodic route advertisement are received, and the source link local address in the periodic route advertisement is obtained, the S-GW Sending the source link local address to the trusted non-3GPP access gateway or ePDG in the proxy binding acknowledgement message; optionally, in this step, the S-GW intercepts the received route advertisement, and obtains the source chain. After the local address is discarded, the route advertisement packet is discarded and is not sent to the MAG. Preferably, after the S-GW obtains the source link local address, the route advertisement sent by the P-GW is not parsed, or the foregoing The route advertisement packet is directly discarded after the route advertisement. Step 406: After the tunnel establishment is completed, the trusted non-3GPP Access or the ePDG notifies the UE of the information about the access network and the configuration information required by the UE (such as an IP address or an IP address prefix, an interface identifier) to complete the IP access of the UE. process. In the subsequent access process, the UE will use the interface identifier obtained from the MAG to generate a link-local address on the local link, and the MAG (ie, trusted Non 3 GPP Access or ePDG) 4 captures the local link between the UE and the UE. The above-mentioned source link local address sent by the S-GW is used as its own link-local address on the road, and the link-local address between the UE and the MAG will not collide. The basic procedure of sending a route advertisement by using the foregoing second method is similar to the foregoing process. The main difference is that if the second method is used to send a route advertisement, in the foregoing step S404, the P-GW only replies to the S-GW to establish a default bearer. In response, instead of sending a route advertisement to the S-GW, after receiving the default bearer response sent by the P-GW, the S-GW sends a route request to the P-GW, where the source link address in the route request is established. The P-GW replies to the route advertisement after receiving the route request by the UE interface identifier in the default bearer response message. If the S-GW does not receive the route advertisement within the predetermined time period, the S-GW may continue to send the route request to P-GW; The S-GW does not send a route request after receiving the route advertisement. Since the P-GW sends the route advertisement according to the route request of the S-GW, the route notification is no longer sent by the jt匕P-GW. . After obtaining the source link local address from the route advertisement sent by the P-GW, the S-GW discards the route advertisement data packet and does not send the route to the MAG, and the S-GW does not send a route request to the P-GW, so that the P- -GW also no longer sends route advertisements. According to an embodiment of the invention, a service gateway is also provided. FIG. 5 is a schematic structural diagram of a service gateway according to an embodiment of the present invention. As shown in FIG. 5, a service gateway according to an embodiment of the present invention mainly includes: a receiving module 51, a parsing module 53, and a sending module 55. The receiving module 51 is configured to receive a data packet from a packet data network gateway, where the data packet includes a route advertisement, and the parsing module 53 is connected to the receiving module 51, and is configured to parse the route in the data packet received by the receiving module 51. The notification module is configured to obtain the source link local address of the ePDG. The sending module 55 is connected to the parsing module 53 and configured to carry the obtained source link local address as a trusted non-3GPP access network or a link local address of the ePDG. The proxy binding acknowledgement message is sent to the trusted non-3GPP access gateway or ePDG. Further, the receiving module 51 is further configured to receive a setup default bearer response from the data network gateway. Further, the sending module 55 may be further configured to send a routing request to the P-GW to request the P-GW to send the route advertisement. Preferably, as shown in FIG. 6, the service gateway may further include: a intercepting module 57, configured to intercept The route notification received by the receiving module 51 is received, and after the parsing module 53 obtains the source link local address, the data packet of the route advertisement is discarded. According to an embodiment of the invention, a packet data network gateway is also provided. FIG. 7 is a schematic structural diagram of a packet data network gateway according to an embodiment of the present invention. As shown in FIG. 7, a packet data network gateway according to an embodiment of the present invention mainly includes: a receiving module 71, an establishing module 73, and a sending module 75. The receiving module 71 is configured to receive a default load request sent by the monthly gateway or receive a routing request from the S-GW. The establishing module 73 is connected to the receiving module 71, and is configured to establish a GTP from the packet data network gateway to the serving gateway. The U-tunnel and the GTP-C tunnel; the sending module 75 is connected to the establishing module 73, and is configured to periodically send a route advertisement through the GTP-U tunnel, or send a route advertisement according to the received routing request, and send through the GTP-C tunnel. Establish a default bearer response. As described above, with the technical solution provided by the embodiment of the present invention, after receiving the establishment of the default bearer request, the P-GW does not need to send a GTC-C message to the S-GW, but sends a periodic route advertisement to the S-GW. The S-GW can obtain the link-local address on the local link between the MAG (including the trusted non-3GPP access network or the ePDG) and the UE by parsing the source link local address of the periodic route advertisement, and does not need to be extended. The interface between the P-GW and the S-GW reduces the requirements on the interfaces of the P-GW and the S-GW, reducing the cost and implementation complexity. In addition, in the embodiment of the present invention, after the S-GW receives the setup default bearer response sent by the P-GW, the S-GW sends a routing request to the P-GW, where the source link address in the routing request is established. The P-GW sends a route request to the P-GW after receiving the route request, and the S-GW receives the route request and sends a route request to the P-GW. The S-GW receives the route request. After the route advertisement is sent, the route request is no longer sent, and the P-GW does not need to send the route advertisement. This reduces the unnecessary route advertisements caused by the P-GW periodically sending route advertisements. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A chain connection establishment method for a user equipment UE to connect to a non-3GPP access network or an evolved packet data gateway ePDG while roaming, and then to a service gateway S-GW of a public land mobile network of a visited network A packet data network gateway P-GW belonging to the public land mobile network HPLMN, characterized in that the authentication 4 authorized charging agent determines to use the chain connection ^! In the case of the service access of the UE, in the case of the HPLMN, the method includes:

Receiving, by the S-GW, the route advertisement sent by the P-GW through the established GPRS tunneling protocol user plane GTP-U tunnel, parsing and obtaining the source link local address of the route advertisement;

The S-GW sends the source link local address in a proxy binding acknowledgement message to a trusted non-3GPP access gateway or ePDG, so that the trusted non-3GPP access gateway or ePDG is in the same manner as the UE Local link communication with the UE using the source link local address on the local link.

The method according to claim 1, wherein before the S-GW receives the route advertisement, the method further includes:

After receiving the setup default bearer request sent by the S-GW, establishing a GTP control plane GTP-C tunnel and the GTP-U tunnel from the P-GW to the S-GW, the P-GW passes the The GTP user plane tunnel periodically sends the route advertisement to the S-GW.

The method according to claim 2, wherein, before the S-GW sends the proxy binding acknowledgement message, the method further includes:

The S-GW receives the setup default bearer response.

The method according to claim 2, wherein after the S-GW receives the route advertisement, the method may further include:

The S-GW intercepts the received route advertisement, and after the source link local address is obtained, discards the data packet of the route advertisement, and the S-GW continues to detect the P-GW. Route advertisement sent through the GTP-U tunnel and discard the data packet advertised by the route; or

After the S-GW obtains the source link local address, the S-GW does not detect the route advertisement periodically sent by the P-GW.

After receiving the setup default bearer request sent by the S-GW, establishing a GTP-C tunnel and the GTP-U tunnel from the P-GW to the S-GW, the P-GW passes the GTP- The C tunnel sends a default bearer response to the S-GW, where the setup default bearer response carries the interface identifier of the UE;

Generating, by the S-GW, a source link address according to the interface identifier, and sending a routing request to the P-GW according to the source link address;

The P-GW receives the routing request, and sends the route advertisement to the S-GW through the GTP-U tunnel.

The method according to claim 5, wherein, after the P-GW sends the route advertisement, if the S-GW does not receive the route advertisement, the method further includes: The S-GW is located at the source link address, and the routing request is sent to the P-GW again.

The method according to claim 5, wherein, after the S-GW receives the route advertisement, the method further includes:

The S-GW intercepts the received route advertisement, and after obtaining the source link local address, discards the data packet advertised by the route, and does not send the route request to the P-GW. .

The method according to any one of claims 1 to 7, wherein after the S-GW sends the proxy binding acknowledgement message, the method further includes:

The non-3GPP access gateway or ePDG uses the source link local address for local area communication with the UE on a local link with the UE.

9. A service gateway, comprising:

a receiving module, configured to receive a data packet from a packet data network gateway, where the data packet includes a route advertisement;

a parsing module, configured to parse the route advertisement in the data packet received by the receiving module, and obtain a source link local address of the route advertisement; a sending module, configured to carry the source link local address as a trusted non-3GPP access network or a link local address of the ePDG in a proxy binding acknowledgement message, and send the trusted non-3GPP access gateway or the Said ePDG.

10. The service gateway of claim 9 wherein:

The receiving module is further configured to receive a default bearer response sent by the data network gateway.

11. The service gateway of claim 10, wherein

The sending module is further configured to send a routing request to the P-GW to request the P-GW to send the route advertisement.

The service gateway according to claim 9, wherein the service gateway further comprises: a intercepting module, configured to intercept the route advertisement received by the receiving module, and acquire the After the source link local address, the data packet of the route advertisement is discarded.

A packet data network gateway, comprising:

a receiving module, configured to receive a default bearer request sent by the serving gateway or receive a routing request from the S-GW;

Establishing a module, configured to establish a GTP user plane tunnel and a GTP control plane tunnel from the packet data network gateway to the monthly gateway;

And a sending module, configured to periodically send a route advertisement through the GTP user plane tunnel, or send a route advertisement according to the received routing request, and establish a default load response by using the GTP control plane tunneling.