WO2012068837A1

WO2012068837A1 - Method and device for selecting access gateway

Info

Publication number: WO2012068837A1
Application number: PCT/CN2011/074162
Authority: WO
Inventors: 周娜; 赵佑春; 吴瑟; 王卫斌; 霍玉臻; 王静; 王志海
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-11-24
Filing date: 2011-05-17
Publication date: 2012-05-31
Also published as: CN102480528A; CN102480528B

Abstract

A method and device for selecting an access gateway are disclosed in the present invention. The method includes the following steps of: obtaining information of a shunting gateway of a first system which a terminal accesses; and selecting the shunting gateway as the shunting gateway of a second system according to the information of the shunting gateway when the terminal accesses the second system. Use of the present invention can solve the problem of the possibility that the movement continuity of IP shunted data of the terminal can not be assured when the terminal simultaneously accesses a plurality of networks or moves between a plurality of access networks, thus enhancing the user experience.

Description

The present invention relates to the field of communications, and in particular to an access gateway selection method and apparatus. BACKGROUND OF THE INVENTION The 3rd Generation Partnership Project (3GPP) evolved Evolved Packet System (EPS) is an evolved universal mobile communication system terrestrial radio access network (Evolved Universal Terrestrial Radio Access Network) , referred to as E-UTRAN, Mobility Management Entity (MME), Serving Gateway (S-GW), Packet Data Network Gateway (P-Data Network Gateway) GW or PDN GW), Home Subscriber Server (HSS), 3GPP Authentication, Authorization and Accounting (AAA), server and policy The Policy and Charging Rules Function (PCRF) entity and other supporting nodes are composed. FIG. 1a is a schematic diagram 1 of an EPS system architecture according to the related art. As shown in FIG. 1a, the mobility management entity is responsible for control planes such as mobility management, non-access stratum signaling processing, and user mobility management context management. The offload gateway S-GW is an access gateway device connected to the E-UTRAN, and forwards data between the E-UTRAN and the P-GW, and is responsible for buffering the paging waiting data; the access gateway P-GW is the EPS A border gateway with a Packet Data Network (PDN), which is responsible for PDN access and forwarding data between the EPS and the PDN; both the S-GW and the P-GW belong to the core network gateway. The home base station is a small, low-power base station that is deployed in indoor locations such as homes and offices. Figure lb is a schematic diagram of the architecture of the existing communication system. As shown in Figure lb, the home base station can access the core network through the home network gateway gateway (the home base station gateway can also be combined with the home base station), or Connect directly to the core network (as shown in Figure la;). In addition to supporting the access of the mobile core network, the mobile communication system (including the home base station system) can also support the network protocol (Internet Protocol, IP for short) offload function, and the IP side of the network element on the wireless side can be configured to allow IP splitting. Under the condition, the terminal can access the local IP address of other IP devices or the Internet of the home network. IP shunting in the systems shown in Figure la and Figure lb can provide IP offloading by adding a shunt gateway to implement IP offloading. As a gateway for external access to an external network (such as the Internet), the traffic distribution gateway provides address allocation, accounting, packet filtering, policy control, data offloading, and radio access network application part (Radio Access Network Application Part, referred to as NAS). /S 1-AP/RANAP ) / General Tunneling Protocol (GTP) / Proxy Mobile IP (PMIP) / Mobile IP (Mobile IP, MIP for short) message parsing, Network Address Translation (NAT), IP offloading policy routing and execution. The offload gateway can also be combined with the wireless side network element. The traffic distribution gateway may be an integrated service gateway (ISGW), and may be a local service gateway (Local SGW, referred to as L-SGW) and a local packet data gateway (Local PGW, referred to as L-PGW). It can be a separate L-PGW, which can be a data offload function entity. Taking the communication system of the La as an example, the IP offloading can be implemented by adding or not adding a NAT address conversion function on the distribution gateway, and is not limited to the simultaneous access of the core network and the IP offloading through a connection. In addition, the terminal can access the network simultaneously or move in multiple access systems through multiple access technologies. At this time, the traffic can be anchored at the traffic distribution gateway to facilitate the flow migration or switching operation of the IP traffic distribution service data. In the case that there is a traffic distribution gateway between the mobility management entity and the access gateway to implement service offloading, in the related art, when the terminal accesses multiple networks at the same time or moves between multiple access networks, the terminal IP is offloaded. Data movement continuity may not be guaranteed. SUMMARY OF THE INVENTION A primary object of the present invention is to provide an access gateway selection method and apparatus to solve at least the above problems. According to an aspect of the present invention, an access gateway selection method is provided, including: acquiring information of a traffic distribution gateway of a first system accessed by a terminal; and when the terminal accesses the second system, according to the traffic distribution The information of the gateway selects the offload gateway as a offload gateway of the second system. Obtaining, by the terminal, the information about the offloading gateway of the first system that is accessed by the terminal, where the terminal obtains the information of the traffic distribution gateway by sending a query request, where the query request is used to query the traffic distribution gateway information. Before the terminal sends the query request, the method further includes: sending the indication information to the terminal, where the indication information is used to instruct the terminal to send the query request. In the case that the first system is a 3rd Generation Partnership Project 3GPP system, transmitting the indication information to the terminal includes: the mobility management entity sends a Packet Data Protocol PDP Context Activation Response message to the terminal via the radio side network element. The PDP context activation response message carries the indication information. In the case that the second system is a wireless local area network WLAN system, selecting the distribution gateway as the distribution gateway of the second system according to the information of the distribution gateway includes: the terminal between the tunnel termination gateway TTG and the tunnel termination gateway TTG The information about the offload gateway is sent to the TTG during the establishment of the secure tunnel; the TTG selects the offload gateway as the offload gateway of the second system according to the information of the offload gateway. In the case that the first system is a WLAN system, sending the indication information to the terminal includes: in a process of performing a secure tunnel establishment, the TTG sends a message to the terminal, where the message carries the indication information . In the case that the second system is a 3GPP system, selecting the offload gateway as the offload gateway of the second system according to the information of the offload gateway includes: sending, by the terminal, a PDP context activation message to the radio side network element a mobility management entity, where the PDP context activation message carries information of the offload gateway; the mobility management entity selects the offload gateway as a offload gateway of the second system according to information of the offload gateway . The mobility management entity is at least one of the following: a mobility management entity MME, a mobile switching center MSC, a monthly service radio packet support node SGSN, and a home base station gateway; and the radio side network element is at least one of the following: Base station, shunt gateway, shunt function entity, home base station, radio network controller RNC, home base station gateway. The offloading gateway includes: a split access gateway and/or a split service gateway, where the offload access gateway is a local packet data gateway L-PGW or a local monthly service radio packet support node L-GGSN; The offloading service gateway is a local serving gateway L-SGW or a local serving general packet radio service supporting node L-SGSN. The offload gateway is at least one of the following: an integrated service gateway ISGW, an L-SGW and an L-PGW, a separate L-PGW, an L-GGSN, and an L-SGSN, a separate L-GGSN, and a data offloading functional entity. The physical location of the offload gateway is close to a wireless network, a user, or a user attachment point. The offload gateway implements the functions of the serving gateway S-GW and/or the packet data network gateway P-GW. According to another aspect of the present invention, an access gateway selecting apparatus is provided, including: an obtaining module, configured to acquire information of a branching gateway of a first system accessed by a terminal; and an access module configured to be connected at the terminal When the second system is entered, the offload gateway is selected as the offload gateway of the second system according to the information of the offload gateway. According to the present invention, the information of the offload gateway of the first system accessed by the terminal is obtained. When the terminal accesses the second system, the offload gateway is selected as the offload gateway of the second system according to the information of the offload gateway. It solves the problem that when the terminal accesses multiple networks at the same time or moves between multiple access networks, the mobility continuity of the terminal IP offload data may not be guaranteed, and the user body-risk is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a schematic diagram of a wireless communication network connection according to the related art; FIG. 1 b is a schematic diagram of a wireless communication network connection according to the related art; FIG. 2 is a schematic diagram of a wireless communication network connection according to the related art; A flowchart of an access gateway selection method according to an embodiment of the present invention; FIG. 4 is a structural block diagram of an access gateway selection apparatus according to an embodiment of the present invention; FIG. 5 is an initial access according to an embodiment of the present invention. A flowchart of a process of accessing a WLAN system after a 3GPP system; FIG. 6 is a flowchart of a process of accessing a 3GPP system after initial access to a WLAN system according to an embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. In the implementation of the embodiment, it is found that for the access or mobile process, since the offloading gateway needs to be anchored, it is possible to select different offload gateways for multiple access systems in the related art, thereby failing to implement terminal IP. The function of offloading data mobility continuity, that is, the requirement of the same selection of the branching gateways in multiple access systems cannot be met in the related art. In this embodiment, the unique selection problem of the offload gateway is considered, and a technical solution for realizing the problem of selecting the offload gateway in the multiple access system under the IP offload service architecture is proposed. FIG. 3 is an access according to an embodiment of the present invention. A flowchart of the gateway selection method, as shown in FIG. 3, the process includes the following steps: Step S302: Obtain information (for example, FQDN and/or IP address) of the offload gateway of the first system accessed by the terminal; Step S304, When the terminal accesses the second system, the traffic distribution gateway is selected as the traffic distribution gateway of the second system according to the information of the traffic distribution gateway. Through the above steps, the existing problems in the related technologies are solved, and the unique selection of the IP offload data gateway can be realized, and the user experience is effectively enhanced. Preferably, in implementation, the terminal may obtain the information of the offload gateway of the first system, and of course, other network elements may obtain the information, regardless of which network element obtains the information of the offload gateway, as long as the terminal When accessing the second system, it is ensured that the shunt gateway can be selected as the shunt gateway of the second system according to the information of the shunt gateway, and the same purpose or effect can be achieved. The following takes the terminal to obtain the information of the traffic distribution gateway as an example for description. The terminal may obtain the information of the offload gateway by sending a query request, where the query request is used to query the information of the offload gateway. The manner of obtaining the terminal may be that the terminal acquires the information actively, and may also send the indication information to the terminal. The indication information is used to instruct the terminal to send the query request. After receiving the indication information, the terminal sends the query request. For example, in a case where the first system is a 3rd Generation Partnership Project 3GPP system, a packet data protocol PDP context activation response message may be sent by the mobility management entity to the terminal via the radio side network element, where the PDP context activation response message is Carry instructions. For example, in a case where the first system is a WLAN system, the TTG may send a message to the terminal in the process of performing the secure tunnel establishment, where the message carries the indication information. The following two examples illustrate how the second system chooses the offload gateway. For example, in the case that the second system is a wireless local area network WLAN system, the terminal sends the information of the distribution gateway to the TTG during the process of establishing a secure tunnel between the terminal and the tunnel termination gateway TTG; the TTG selects the distribution gateway according to the information of the distribution gateway. The shunt gateway of the second system. For example, in a case where the second system is a 3GPP system, the terminal may send a PDP context activation message to the mobility management entity via the radio side network element, where the PDP context activation message carries information of the offload gateway; the mobility management entity The information of the home streaming gateway selects the traffic distribution gateway as the traffic distribution gateway of the second system. Preferably, the mobility management entity is at least one of the following: a mobility management entity MME, a mobile switching center MSC, a serving general packet radio service supporting node SGSN, a home base station gateway; and a wireless side network element is at least one of the following: a traffic distribution gateway, Shunt function entity, home base station, radio network controller RNC, home base station gateway. An access gateway selection device is also provided in this embodiment, and the device is used to implement the foregoing embodiments and preferred embodiments thereof. The descriptions of the modules involved in the device are described below. . FIG. 4 is a structural block diagram of an access gateway selection apparatus according to an embodiment of the present invention. As shown in FIG. 4, the structure includes: an obtaining module 42 and an access module 44. This will be explained below. The obtaining module 42 is configured to obtain information about the offload gateway of the first system accessed by the terminal; the access module 44 is connected to the obtaining module 42, and the module is configured to: when the terminal accesses the second system, the information of the shunt gateway is obtained. The offload gateway is selected as the offload gateway of the second system. The preferred embodiments are described below. The following preferred embodiment describes a terrestrial radio access network based on a universal mobile communication system (Universal

Terrestrial Radio Access Network (referred to as UTRAN) system application scenario. FIG. 5 is a flowchart of a process of accessing a WLAN system after initial access to a 3GPP system according to an embodiment of the present invention. As shown in FIG. 5, the process includes the following steps: Step S501: A terminal sends a PDP context activation message by using a radio side network element. To the mobility management entity; step S502, the mobility management entity requests the offload gateway to perform context establishment; step S503, the PDP context establishment process is performed between the offload gateway and the access gateway; and in step S504, the gateway responds to the context of the mobility management entity Establish a response; Step S505, the mobility management entity returns a PDP context activation response to the terminal via the radio side network element, and may carry the identifier information, where the information is used to notify the terminal to initiate a diversion gateway information query message, such as a DNS request, step S506, where the terminal is established. The sending and receiving gateway information query request may be carried, and may carry a special access point name (Access Point Name, abbreviated as ΑΡΝ); Step S507, the branching gateway receives or intercepts the shunt gateway information query request; Step S508, the shunt gateway receives or intercepts After the information about the offload gateway information query request, the information about the offload gateway, such as the FQDN or/and the IP address, is returned to the terminal. In step S509, after the terminal enters the WLAN coverage, the service set identifier (Service Set Identifier, SSID) is selected. And automatically associated with the WLAN; Step S510, if the terminal saves the temporary identifier, the temporary identifier is used, otherwise the NAI is constructed according to the International Mobile Subscriber Identification Number (IMSI), and the EAP authentication for accessing the WLAN is initiated. Process; step S511, after successful authentication, pass The Dynamic Host Configuration Protocol (DHCP) obtains the IP address assigned by the WLAN network and the DNS server address. In step S512, the terminal performs DNS query according to the pre-configured domain name to obtain the TTG (Tunnel Termination). The IP address of the gateway (Terminal Termination Gateway); Step S513, the security tunnel establishment process is performed between the terminal and the TTG; wherein the terminal sends the information of the traffic distribution gateway to the Tunnel Termination Gateway (TTG). If the offload gateway information saved by the terminal is an IP address, the terminal may obtain the FQDN of the offload gateway according to the IP lookup according to the IP address. In step S515, the TTG obtains the offload gateway address according to the offload gateway information. If the offload gateway information is the FQDN, the TTG queries the DNS server to obtain the offload gateway address. If the offload gateway information is an IP address, the TTG can directly obtain the IP address as the offload gateway address; Step S516, the TTG to the offload gateway Sending a PDP context establishment request, and the offload gateway returns a PDP context establishment response to the TTG to perform a PDP context establishment procedure; Step S517, continuing to perform the security tunnel establishment process; Step S518, the terminal sends a SIP registration message to the offload gateway, and performs an authentication process. The offload gateway returns PCC policy information to the terminal. FIG. 6 is a flowchart of a process of accessing a 3GPP system after initial access to a WLAN system according to an embodiment of the present invention. As shown in FIG. 6, the process includes the following steps: Step S601: After the terminal enters WLAN coverage, select an appropriate SSID. And automatically associated with the

WLAN; Step S602: If the terminal saves the temporary identifier, the terminal uses the temporary identifier. Otherwise, the NAI is configured according to the IMSI, and the EAP authentication process for accessing the WLAN is initiated. Step S603, after the authentication succeeds, the IP address and DNS allocated by the WLAN network are obtained through DHCP. In step S604, the terminal performs a DNS query according to the pre-configured domain name to obtain the IP address of the TTG. Step S605: The secure tunnel establishment process is performed between the terminal and the TTG. The terminal sends the APN information to the TTG. Step S606, TTG Obtaining the selection unit address according to the APN, the selection unit acquires the distribution gateway address according to the location information; Step S607, the TTG sends a PDP context establishment request to the selection unit, and the selection unit forwards the PDP context establishment request to the distribution gateway; after the distribution gateway selects the access gateway Sending a PDP context establishment request to the access gateway; Step S608, after receiving the PDP context setup response message replied by the access gateway, the offload gateway sends a PDP context setup response to the selecting unit, and the selecting unit sends a PDP context setup response message to the TTG. Can carry offload gateway tunnel information , such as a tunnel identifier, an address, to establish a tunnel between the TTG and the offload gateway; Step S609, continue to perform the secure tunnel establishment process. The message sent by the TTG to the terminal may carry the identifier information, where the information is used to inform the terminal to initiate the offload gateway information query message, such as a DNS request; Step 4: S610, the terminal sends the offload gateway information query request on the established connection, Carry a special APN; Step S612, the sinking gateway receives (or intercepts) the information about the branch gateway information query, and returns information of the branching gateway, such as an FQDN or/and an IP address, to the terminal. Step S613: The terminal sends a SIP registration message to the offload gateway, and performs authentication. process. The offloading gateway returns the PCC policy information to the terminal; Step S616, the terminal enters the 3GPP coverage area, and sends a PDP context activation message to the mobility management entity via the radio side network element, and carries the information of the offload gateway, such as the FQDN or/and the IP address; Step S617 The mobility management entity obtains the offload gateway address according to the offload gateway information. If the offload gateway information is an FQDN, the mobility management entity queries the DNS server to obtain the offload gateway address; if the offload gateway information is an IP address, the mobility management entity may directly obtain the IP address as a branch address; Step S618, the mobility management entity sends a PDP context establishment request to the offload gateway; Step S619, the PDP context establishment process is performed between the offload gateway and the access gateway; Step S620, the gateway responds to the mobility management entity with a context establishment response; S621. The mobility management entity returns a PDP context activation response to the terminal via the radio side network element. In the above embodiment, step S617 may also be used in the following manner: after the mobility management entity obtains the selection unit through the APN, the selection unit acquires the distribution gateway address according to the offload gateway information. The mobility management entity sends a PDP context establishment request to the selection unit. The selecting unit forwards the PDP context establishment request to the branching gateway. Correspondingly, step S618, step S619 and step S620 need to adopt the following manner: after receiving the PDP context setup response message replied by the access gateway, the offload gateway sends the selection gateway to the selecting unit. The PDP context establishment response, the selecting unit sends a PDP context setup response message to the mobility management entity, and may carry the offload gateway tunnel information, such as the tunnel identifier and the address, for establishing a tunnel between the radio side network element and the offload gateway. In order to simplify the description, the above embodiment only uses the case of FIG. 2 as an example to illustrate the manner in which the serving gateway performs relocation in the IP offload connection communication system. In the case of the system of FIG. 1 and FIG. 1b, the flow of selecting the offload gateway is similar to that of the above embodiment, regardless of the E-UTRAN or UTRAN system, and therefore will not be described again. In the above embodiment, the network element TTG may also be replaced by a PDG (Packet Data Gateway), ePDG (Evolved Packet Data Gateway) network element. At this time, the process of selecting the branching gateway is similar to the above embodiment, and therefore will not be described. It should be noted that, in all the above embodiments, the TTG and the offload gateway may be combined or divided. In addition, it should be noted that the offload gateway may be an ISGW, may be an L-SGW and an L-PGW, may be a separate L-PGW, may be an L-GGSN and an L-SGSN, and may be a separate L-GGSN. , can be a data offload function entity. The offload gateway includes a split access gateway and/or a offload service gateway; the offload access gateway is an L-PGW or an L-GGSN; and the offload monthly gateway is an L-SGW or an L-SGSN. The physical location of the offload gateway can be close to the wireless network or user or user attachment point. The offload gateway can implement the functions of the serving gateway S-GW and/or the packet data network gateway P-GW. The offload gateway may be a monthly service gateway S-GW and/or a packet data network gateway P-GW located close to the wireless network or a user or user attachment point. The wireless side network element may be a base station, a home base station, an RNC, a offload gateway, a offload function entity, and a home base station gateway. The mobility management entity may be an MME, an MSC, an SGSN, or a home base station gateway. The access gateway may be a core network access gateway, which may be a split access gateway; the monthly service gateway may be a core network service gateway, and may be a offload service gateway. The core network access gateway is a P-GW or a GGSN; the core network service gateway is an S-GW or an SGSN.

IP offloading can be local IP access to the user's local network, local IP access to the company's local network, local IP access to the Internet, Internet traffic shunting, and specific IP data offloading. In summary, the above embodiment solves the problem of selecting a split gateway in a multi-access system under the IP offload service architecture, and realizes the unique selection of the IP offload gateway, thereby effectively enhancing the user experience. 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 so that they may be stored in the storage device by the computing device, or they may be separately fabricated into individual integrated circuit modules, or Multiple modules or steps are made into 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 present invention, and various modifications and changes can be made to the present invention. Where in the invention ^" God and principle Any modifications, equivalent substitutions, improvements, etc. made therein are intended to be included within the scope of the present invention.

Claims

Claim

1. An access gateway selection method, including:

Obtaining information of the offload gateway of the first system accessed by the terminal;

When the terminal accesses the second system, the branch gateway is selected as the offload gateway of the second system according to the information of the offload gateway.

2. The method according to claim 1, wherein the obtaining information of the offload gateway of the first system accessed by the terminal comprises:

The terminal obtains the information of the offload gateway by sending a query request, where the query request is used to query information of the offload gateway.

The method of claim 2, wherein, before the terminal sends the query request, the method further includes:

And sending the indication information to the terminal, where the indication information is used to instruct the terminal to send the query request.

The method according to claim 3, wherein, when the first system is a 3rd Generation Partnership Project 3GPP system, sending the indication information to the terminal includes:

The mobility management entity sends a packet data protocol PDP context activation response message to the terminal via the radio side network element, where the PDP context activation response message carries the indication information.

The method according to any one of claims 2 to 4, wherein, in a case where the second system is a wireless local area network WLAN system, the distribution gateway is selected as the location according to the information of the distribution gateway The offloading gateway of the second system includes:

Transmitting, by the terminal, the information of the offload gateway to the TTG during a secure tunnel establishment process between the terminal and the tunnel termination gateway TTG;

The TTG selects the offload gateway as the offload gateway of the second system according to the information of the offload gateway.

The method according to claim 3, wherein, when the first system is a WLAN system, sending the indication information to the terminal includes: The TTG sends a message to the terminal, where the message carries the indication information.

The method according to claim 2, 3 or 6, wherein, in a case where the second system is a 3GPP system, the traffic distribution gateway is selected as the second system according to information of the traffic distribution gateway The offloading gateway includes:

The terminal sends a PDP context activation message to the mobility management entity via the radio side network element, where the PDP context activation message carries the information of the offload gateway; the mobility management entity resides in the information of the offload gateway The offload gateway is selected as the offload gateway of the second system.

8. The method according to claim 4 or 7, wherein

The mobility management entity is at least one of the following: a mobility management entity MME, a mobile switching center MSC, a monthly general radio service support node SGSN, and a home base station gateway;

The wireless side network element is at least one of the following: a base station, a traffic distribution gateway, a traffic distribution function entity, a home base station, a radio network controller RNC, and a home base station gateway.

The method according to claim 1, wherein the offload gateway comprises: a split access gateway and/or a split monthly gateway, wherein the offload access gateway is a local packet data gateway L-PGW or local The general-purpose packet radio service supporting node L-GGSN; the shunting service gateway is a local monthly service gateway L-SGW or a local monthly general-purpose packet radio service supporting node L-SGSN.

10. The method according to claim 1, wherein the offload gateway is at least one of: an integrated service gateway ISGW, an L-SGW and an L-PGW, a separate L-PGW, an L-GGSN, and an L-SGSN, Separate L-GGSN, data offloading functional entity.

11. The method according to claim 1, wherein the physical location of the offload gateway is close to a wireless network, a user or a user attachment point.

The method according to claim 1 or 11, wherein the offload gateway implements functions of a serving gateway S-GW and/or a packet data network gateway P-GW.

13. An access gateway selection device, comprising:

Obtaining a module, configured to obtain information about a distribution gateway of the first system accessed by the terminal; The access module is configured to select the offload gateway as the offload gateway of the second system according to the information of the offload gateway when the terminal accesses the second system.