CN105813153B - Inter-network switch method, network element and system - Google Patents

Abstract

The present invention discloses a kind of inter-network switch method, network element and system.This method comprises: access network discovery and selection function ANDSF server send across a network switch prompting to the ANDSF client of user equipment (UE) according to strategy；ANDSF server receives switching command and user information from UE；ANDSF server sends switching instruction according to switching command and user information and arrives target network；ANDSF server notice UE executes across a network switching so that UE is switched to target network.Inter-network switch method, network element and the system that the disclosure provides, the switching command initiated according to ANDSF client on UE, ANDSF server can carry out across a network system switching, and, can under the premise of retaining IP address handover network, it ensure that the business continuance of requirement of real-time height application, and introduce APP ad hoc mode to realize the dominance that user switches across a network, improve user experience.

Description

Inter-network switch method, network element and system

Technical field

The present invention relates to the communications field more particularly to a kind of inter-network switch methods, network element and system.

Background technique

WLAN (Wireless Local Area Networks, WLAN) and LTE (Long Term in recent years Evolution, long term evolution) combination network is in 3GPP (The 3rd Generation Partnership Project, third For partner program) SaMOG is proposed in normal structure, and (S2a Mobility based on GTP, the S2a based on GTP are moved Dynamic property) networking plan.Current network capabilities and terminal capability belongs to transparent single connection mode (Transparent Single-Connection mode), which is the connection side of definition WLAN and LTE collaboration networking after 3GPP R12 version One of formula, still, terminal can not initiate the switching of cross-system under the connection type at this stage.

Therefore, it is necessary to a kind of inter-network switch method be proposed, so that terminal can be sent out in WLAN and LTE combination network It rises and realizes that cross-system switches.

Summary of the invention

The disclosure technical problem to be solved is to initiate terminal can in WLAN and LTE combination network And realize that cross-system switches.

The disclosure provides a kind of inter-network switch method, comprising: access network discovery and selection function ANDSF server root Across a network switch prompting is sent to the ANDSF client of user equipment (UE) according to strategy；ANDSF server receives the switching from UE Instruction and user information；ANDSF server sends switching instruction according to switching command and user information and arrives target network； ANDSF server notice UE executes across a network switching so that UE is switched to target network.

Further, user information includes international mobile subscriber identity IMSI, access point name APN, network protocol IP Address；It includes: that ANDSF is serviced that ANDSF server, which sends switching instruction to target network according to switching command and user information, Device sends the controller that target network is arrived in switching instruction according to switching command and user information, to trigger packet data gateway P-GW establishes the connection of UE and target network based on IP address.

Optionally, the connection that P-GW establishes UE and target network based on IP address includes: that P-GW receives switching instruction, judgement Whether it is that UE distributed IP address, if distributing IP address, the connection of UE and target network is established using identical IP address.

Optionally, when UE is switched to WLAN WLAN from long term evolution LTE, controller is third generation affiliate meter Draw verifying, authorization and accounting 3GPP AAA, ANDSF server sends switching instruction according to switching command and user information and arrives mesh It marks network-based control device, include: that ANDSF server will to trigger the connection that P-GW establishes UE and target network based on IP address Switching instruction including user information is sent to 3GPP AAA；3GPP AAA executes switching access WLAN and initiate extension in UE to be recognized When demonstrate,proving protocol authentication process, it is based on user IMSI (International Mobile Subscriber Identification Number, international mobile subscriber identity) giving TWAG (trusted wireless LAN access gateway, credit WLAN access gateway) authorization messages in insertion switching instruction, type of attachment is changed to switching request；P-GW receive TWAG according to After the session establishment request that switching request is sent, identical IP address is distributed for UE；P-GW is by its own P-GW mark and APN Information passes to 3GPP aaa server, obtains authentication information from 3GPP AAA；P-GW sends session establishment response, by IP address It is sent to UE, IP address is the IP address that UE is used in LTE access.

Optionally, when UE is switched to long term evolution LTE from WLAN WLAN, controller is mobile management entity MME, ANDSF server sends switching according to switching command and user information and indicates the controller to target network, to trigger P- GW includes: that switching instruction and user information are issued to by ANDSF server based on the connection that IP address establishes UE and target network MME；MME receives the IMSI insertion switching instruction based on user after the attach request of UE, and attach request is changed to switching request； MME authenticates UE according to HSS (Home Subscriber Server, home subscriber server), if authenticating successfully, MME Execution position updates and subscription data acquisition process；P-GW sends session establishment request according to MME and sends session establishment response, meeting It includes that UE accesses the IP address used in WLAN that words, which are established in response,.

Optionally, it includes time, position, wlan network load and quality, LTE network load and matter that method, which includes: strategy, Amount uses application type.

The disclosure also provides a kind of network element, comprising:

Sending module, for sending across a network switch prompting to the ANDSF client of user equipment (UE) according to strategy；It receives Module, for receiving switching command and user information from UE；Processing module is used to be believed according to switching command and user Breath generates switching instruction, sends target network for switching instruction by sending module；Sending module is also used to that UE is notified to execute Across a network switching is switched to target network so as to UE.

Further, user information includes international mobile subscriber identity IMSI, access point name APN, network protocol IP Address, sending module are used for: the controller that target network is arrived in switching instruction is sent according to switching command and user information, thus Triggering packet data gateway P-GW establishes the connection of UE and target network based on IP address；And/or strategy include the time, position, Wlan network load and quality, LTE network load and quality use application type.

The disclosure also provides a kind of across a network switching system, comprising: such as said network element；

ANDSF client, for receive network element according to strategy send across a network switch prompting, send switching command and User information is to network element；P-GW is indicated for receiving switching, is judged whether it is UE and distributed IP address, if distributing IP address, The connection of UE and target network is then established using identical IP address；Third generation partner program verifying, authorization and accounting 3GPP AAA, for controlling UE access WLAN；Controller is mobile management entity MME, for controlling UE access LTE.

Optionally, UE is switched to WLAN WLAN from long term evolution LTE, comprising:

Network element is used to the switching instruction including user information being sent to 3GPP AAA；3GPP AAA is used to cut in UE execution When changing-over enters WLAN and initiates Extensible Authentication Protocol authentication process, it is inserted into and is cut in the authorization messages to TWAG based on user IMSI Instruction is changed, type of attachment is changed to switching request；P-GW is used to receive TWAG and is requested according to the session establishment that switching request is sent Afterwards, identical IP address is distributed for UE；P-GW is used to its own P-GW mark and APN information passing to 3GPP AAA service Device obtains authentication information from 3GPP AAA；IP address is sent to UE, IP address is for sending session establishment response by P-GW The IP address that UE is used when LTE is accessed.

Optionally, UE is switched to long term evolution LTE from WLAN WLAN, comprising:

Network element is issued to MME for that will switch instruction and user information；MME is based on after being used to receive the attach request of UE The IMSI insertion switching instruction of user, is changed to switching request for attach request；MME is for authenticating UE according to HSS, if recognizing It demonstrate,proves successfully, MME execution position updates and subscription data acquisition process；P-GW is used to send session establishment request according to MME and send Session establishment response includes that UE accesses the IP address used in WLAN in session establishment response.

Inter-network switch method, network element and the system that the disclosure provides, the switching initiated according to ANDSF client on UE Instruction, ANDSF server can carry out across a network switching.

Detailed description of the invention

Fig. 1 shows the flow chart of the inter-network switch method of one embodiment of the invention.

Fig. 2 shows the S2a of one embodiment of the invention and S2b networking plan schematic diagram.

Fig. 3 shows the ANDSF configuration diagram under the non-roaming scene of one embodiment of the invention.

The LTE that Fig. 4 A shows one embodiment of the invention cooperates with networking schematic diagram with WLAN.

Fig. 4 B shows the interface diagram between the ANDSF Server of one embodiment of the invention and 3GPP AAA, MME.

Fig. 5 A shows the ANDSF workflow schematic diagram of one embodiment of the invention.

Fig. 5 B shows the ANDI policy information child node schematic diagram of one embodiment of the invention.

Fig. 5 C shows the ISMP policy information child node schematic diagram of one embodiment of the invention.

The DNS mode that Fig. 6 shows one embodiment of the invention carries out the flow diagram of ANDSF discovery.

Fig. 7 shows the flow diagram that message transport occurs between the ANDSF Server and UE of one embodiment of the invention.

Fig. 8 shows the hand-off process flow diagram of LTE to the WLAN of one embodiment of the invention.

Fig. 9 shows the hand-off process flow diagram of WLAN to the LTE of one embodiment of the invention.

Figure 10 shows the structural schematic diagram of the network element of one embodiment of the invention.

Figure 11 shows the structural schematic diagram of the across a network switching system of one embodiment of the invention

Specific embodiment

With reference to the accompanying drawings to invention is more fully described, wherein illustrating exemplary embodiment of the present invention.

Fig. 1 shows the flow chart of the inter-network switch method of one embodiment of the invention.As shown in Figure 1, this method is main Include:

Step 100, access network discovery and selection function ANDSF server are according to strategy to the ANDSF of user equipment (UE) Client sends across a network switch prompting.

Step 102, ANDSF server receives switching command and user information from UE.

Step 104, ANDSF server sends switching instruction according to switching command and user information and arrives target network.

Step 106, ANDSF server notice UE executes across a network switching so that UE is switched to target network.

The inter-network switch method of the embodiment of the present invention, according to the switching command that ANDSF client on UE is initiated, ANDSF Server can carry out across a network switching.

In one embodiment, user information includes international mobile subscriber identity IMSI, access point name APN, network association IP address is discussed,

It includes: that ANDSF takes that ANDSF server, which sends switching instruction to target network according to switching command and user information, Business device sends switching instruction according to switching command and user information and arrives the controller of target network, to trigger P-GW based on IP The connection of UE and target network is established in address.

The inter-network switch method of the embodiment of the present invention, can under the premise of retaining IP address handover network, prevent from using Family goes offline or re-registers, and improves user experience.

In implementing one, P-GW includes: based on the connection that IP address establishes UE and target network

Packet data gateway P-GW receives switching instruction, judges whether it is UE and distributed IP address, if distributing IP address, The connection of UE and target network is then established using identical IP address.

The present invention is based on ANDSF frameworks to realize the method for retaining IP address switching between LTE and wlan network, and user passes through ANDSF APP client informs that ANDSF Server will carry out across a network switching, ANDSF Server by with MME or 3GPP The interface of AAA issue switching instruction, from the controller of target network such as MME or 3GPP AAA user to switching target network Insertion switching (handover) indicates during establishing connection, it is ensured that after P-GW detects " handover " instruction, inspection is It is no to give the user the allocated IP address excessively, if the allocated mistake, the identical IP address of use distribute to the user for address It uses.In this manner it is ensured that the terminal of transparent single connection mode is only supported to can be realized LTE and WLAN net under existing process The seamless switching of network ensure that the business continuance that requirement of real-time height is applied, and introduce APP ad hoc mode to realize use The dominance that family switches across a network.

In one embodiment, when UE is switched to WLAN from LTE, controller is 3GPP AAA, and ANDSF server is according to switching Instruction and user information send switching instruction to target network controller, to trigger P-GW be based on IP address establish UE and The connection of target network includes: that ANDSF server indicates the switching including user information to be sent to 3GPP AAA；3GPP AAA When UE executes switching access WLAN and initiates Extensible Authentication Protocol authentication process, disappeared based on user IMSI in the authorization to TWAG Insertion switching instruction, is changed to switching request for type of attachment in breath；Packet data network gateway (PDN Gateway, PDN-GW, Can be abbreviated as P-GW) receive the session establishment request that TWAG is sent according to switching request after, be the identical IP address of UE distribution；P- Its own P-GW mark and APN information are passed to 3GPP aaa server by GW, obtain authentication information from 3GPP AAA；P-GW Session establishment response is sent, IP address is sent to UE.

In one embodiment, when UE is switched to LTE from WLAN, controller is MME (mobile management entity, Mobility Management Entity), ANDSF server sends switching instruction according to switching command and user information and arrives target network Controller, to trigger P-GW based on the connection that IP address establishes UE and target network include: that ANDSF server refers to switching Show and user information is issued to MME；MME receives the IMSI insertion switching instruction based on user after the attach request of UE, will be attached Request be changed to switching request；MME authenticates UE according to HSS, if authenticating successfully, MME execution position updates and signing number According to acquisition process；P-GW sends session establishment request according to MME and sends session establishment response, includes that UE exists in session establishment response WLAN accesses the IP address used.

In one embodiment, strategy include time, position, wlan network load and quality, LTE network load and quality or Use application type；After UE establishes the connection with target network according to the IP address of former network, the connection of release and former network.

In the networking plan of the SaMOG of LTE and WLAN combination network in one embodiment, increase TWAG in a network (Trusted WLAN Access Gateway, credit WLAN access gateway) network element accesses EPC (Enhanced as WLAN Packet Core, enhance core net) access gateway, P-GW (PDN Gateway or Public Data Network Gateway, common data base gateway) it is responsible for the processing of user data package and other networks, become the unification of LTE Yu WLAN business The management node of control, charging and IP address distribution.

WLAN is cooperateed with LTE in 3 gpp defines 3 kinds of schemes, referred to as S2a, S2b, S2c.Fig. 2 shows a realities of the invention Apply S2a and S2b the networking plan schematic diagram of example.Wherein S2a scheme is for WLAN access as credit network insertion to EPC net Network, first line of a couplet P-GW interface are S2a；S2b scheme is for WLAN access as non-credit network insertion to EPC network, i.e. first line of a couplet P- GW interface is S2b.Have in S2a scheme there are two schemes, a kind of scheme is to access net in the non-3 gpp IP of credit In (Trusted Non-3GPP IP Access), to BRAS (the Broadband Remote Access of wlan network Server, Broadband Remote Access Server) or AC (Authentication Center, Authentication Center) network element be transformed branch S2a is held, MIP (Mobile IP, mobile network protocol) agreement or GTP (General Data can be used in S2a interface Transfer Platform, general data transfer platform) agreement, another scheme is to access net in the non-3 gpp IP of credit In, new network element i.e. TWAG is introduced, S2a interface is supported by it, S2a interface is only capable of using GTP agreement, so referred to as SaMOG.

In one embodiment, the technical solution of invention can be applied to will be in entire S2a scheme.

The Three models of WLAN access in 3GPP standard based on SaMOG scheme: transparent single connection mode (Transparent Single-Connection mode), single connection mode (Single-Connection mode), connect more Mode (Multi-Connection mode) is met, can be used for distinguishing the terminal capability for supporting R11 and R12 different phase:

1) transparent single connection mode: the WLAN for being defined as credit establishes the tunnel S2a or (WLAN of non-seamless points of NSWO Stream, Non-seamless WLAN offload) when, there is no the communication mould between the UE of particular/special requirement and the TWAN of credit to terminal Formula；

2) it single connection mode: is defined as at a time only supporting to establish the energy of a connection between UE and the TWAN of credit Power.This connection can be used for NSWO or PDN connection.Single connection mode use and connection relevant parameter (such as: be used for NSWO, for PDN connection, APN etc.) negotiate during the certification of TWAN.

3) multi-connection mode: being defined as at a time can establish a connection between UE and the TWAN of credit, can also be with Establish the ability of a plurality of connection.One connection can be used for NSWO, one or more concurrently connection can be used for PDN connection.It is more The use of connection mode is negotiated during the certification of TWAN, and PDN establishment of connection uses WLCP agreement.

For UE, SaMOG scheme can be divided into two of the UE-Impact to the no-UE-Impact and R12 of R11 A stage:

For the no-UE-Impact stage, it is mainly characterized by comprising:

1) UE before R11 is enhanced without function, comprising:

The processes such as more PDN connections, switching are not supported；

Do not support the information such as transmitting APN, PDN type.

2) scene for accessing EPC and NSWO simultaneously is not supported；

3) the UE function before compatible R11.

For the UE-Impact stage, it is mainly characterized by comprising:

1) the R11 version of compatible SaMOG scheme；

2) processes such as more PDN connections, switching are supported；

3) information such as transmitting APN, PDN type are supported；

4) support while accessing the scene of EPC and NSWO.UE can be indicated to network side its whether support access EPC or NSWO, and network side can also indicate the result of the access EPC or NSWO of decision to UE.

Meanwhile 3GPP TR 23.852 also proposed needs and consider the following scenario:

1) the access control of EPC resources/services is accessed；

2) EPS business seamless mobility between 3GPP and WLAN: IP address is constant；

3) EPS business non-seamless mobility between 3GPP and WLAN: IP address variation；

4) single PDN connection of UE is supported to connect with more PDN；

5) the access EPC and NSWO of WLAN are supported simultaneously.

Connection mode combination terminal capability in the prior art and scene are made further refinement and defined by the present invention:

One connection mode explanation of table

According to above-mentioned analysis it is found that network capabilities and terminal capability belong to transparent single connection mode in the prior art (Transparent Single-Connection mode), terminal can not initiate the switching of cross-system, and network also cannot achieve Retain the switching of IP address between LTE and wlan network, even if version can be by single connection mode (Single- after R12 Connection mode), the support of multi-connection mode (Multi-Connection mode), and utilize EAP-AKA (Extensible Authentication Protocol-Authentication and Key Agreement, extended authentication Protocol-Authentication and key agreement) certification extension is just able to achieve the handoff functionality for retaining IP address between LTE and wlan network, but works as It is preceding not having the terminal and the network equipment for having such ability, it needs under existing network condition, LTE proposed by the present invention Retain the method for IP address switching between wlan network, terminal or network can initiate across a network switching, and cut in across a network When being switched to target network during changing, the original IP address of UE can be retained, prevent user falling in across a network handoff procedure Line problem improves user experience.

Fig. 3 shows the ANDSF configuration diagram under the non-roaming scene of one embodiment of the invention, can increase in network side Add a new ANDSF functional entity such as H-ANDSF 302, it comprises network discoveries and selection for the ANDSF functional entity Relevant data management and control function can be pushed under the triggering of network side to UE 301 by the S14 interface between UE Data can also respond the request of UE as it and transmit data, and the content of transmission is determined by operator.Wherein, H-ANDSF refers to Home-ANDSF (ownership place ANDSF server).

In order to make terminal that can obtain various access nets in advance before executing across rete mirabile switching, (3GPP accesses net and non-3 gpp Access net) relevant information, carried out in advance for terminal network discovery and selection to reduce handover delay, EPC core net introduce ANDSF (Access Network Discovery and Selection Function, access network discovery and selection function Can), increase a new ANDSF functional entity in network side, it can be under the triggering of network side by the S14 interface between UE To UE propelling data, the request of UE can also be responded as it and transmit data, to implement the across a network selection based on strategy or cut It changes.

The LTE and WLAN that Fig. 4 A shows one embodiment of the invention cooperate with networking schematic diagram, and LTE cooperates with networking packet with WLAN Include SaMOG scheme and ANDSF scheme.Increase access gateway of the TWAG network element as WLAN access EPC in a network, this network element is contained TWAG involved in the SaMOG scheme of 3GPP standard and TWAP (Trusted WLANAAA Proxy, credit WLAN AAA are covered Agency) two logical nes function；Increase ANDSF network element, this network element passes through the ANDSF APP client with installation at the terminal The interaction between program is held, realizes network discovery when user's access and selection.

A kind of ANDSF APP client is arranged in the present invention on UE, and can pre-install for terminal to fill later, should APP client implements control management to terminal communication module.By the way that the APP client is arranged in the side UE, user can be made It is capable of the selection network of active or carries out across a network switching, the control that network selects or switches can be handed over into user hand In.

Fig. 4 B shows the interface diagram between the ANDSF Server of one embodiment of the invention and 3GPP AAA, MME, such as Fig. 4 B, the interface are defined as ANDSF Server and are issued to 3GPP AAA, MME with user information for example: IMSI, APN, IP address Etc. binding switching instruction.Meanwhile 3GPP AAA, MME will be performed corresponding processing respectively, wherein 3GPP AAA will be based on IMSI information index will be handed down to type of attachment in the authorization message of TWAG and be changed to " switching attachment ", and MME will be believed based on IMSI It is " initial attached that breath index, which will carry out executing the UE that LTE and WLAN switches to send type of attachment in the Attach Request to come up, " it is revised as " switching attachment ".Subsequent TWAG or MME will be defined by switching flow and be handled.

What the embodiment of the present invention proposed realizes reservation IP address switching between LTE and wlan network based on ANDSF framework Method, user inform that ANDSF Server will carry out across a network switching by ANDSF APP client, and ANDSF Server passes through Switching instruction is issued with the interface of MME or 3GPP AAA, terminal is initiated into normal access request and becomes switching request, by MME Or 3GPP AAA insertion " handover " instruction during user establishes connection to switching target network, it is ensured that P-GW (PDN Gateway, public data network gateway) detect " handover " instruction after, check whether and cross IP to the user is the allocated Location, if the allocated mistake, the identical IP address of use distribute to user use for address.This patent is not necessarily to existing EAP (Extensible Authentication Protocol, Extensible Authentication Protocol) authentication protocol is extended, it is ensured that Only support the terminal of transparent single connection mode can be realized to retain cutting for IP address between LTE and wlan network under existing process It changes, meanwhile, introducing APP ad hoc mode realizes the dominance that user switches across a network.

Fig. 5 A shows the ANDSF workflow schematic diagram of one embodiment of the invention, when user executes switching, Ke Yicong LTE is switched to WLAN, and LTE can also be switched to from WLAN, and Fig. 5 A illustrates the work of ANDSF for being switched to WLAN from LTE Process, as shown in Figure 5A

S501:UE is linked into LTE system.

S502: opening the ANDSF APP client of the side UE, and either client configures IP address in a manner of dns resolution Mode is communicated with the ANDSF Server of network side foundation, this process is ANDSF Discovery (ANDSF discovery procedure)；

S503:ANDSF Server issues the message that can be switched to WLAN based on the position of UE, these strategies can be Time, position, LTE network load and quality and using application type etc. because usually triggering；

S504: it is chosen whether to carry out the switching of cross-system by user oneself.It, will be after if user has selected without switching The connection of LTE is held in continuation of insurance；

S505: if user has selected to switch over, by ANDSF APP client by execute switching determine and use The relevant information (such as: IMSI, APN, IP address) at family is reported to ANDSF Server；

The switching instruction of user bound information is issued in handover target system by S506:ANDSF Server, in this example To be issued on the 3GPP AAA network element of wlan system, the description of Fig. 4 is seen；

S507:ANDSF Server sends switch acknowledgment message to ANDSF APP client, and it is interdepartmental to inform that UE can be executed The switching of system；

S508: the process of cross-system switching is completed.

The ANDSF workflow of the embodiment of the present invention can realize UE cross-system based on the instruction of ANDSF APP client Switching.Inter-system mobility strategy ISMP is provided in ANDSF (to move between inter-system mobility policy system Dynamic property strategy), ANDI access network discovery information (access network discovery information), route between system Road between tactful ISRP (inter-system routing policy) and APN (Access Point Name, access point name) By the information of tactful IARP (inter-APN routing policy) 4 seed types, whole offers are provided, are also possible to only mention For one of which.

Basis of the invention is the transparent single connection mode of SaMOG, at least available three kinds of strategies in ANDSF, packet Include ANDI, ISMP and IARP.ANDSF server sends the prompt that can be switched over according to strategy to ANDSF APP client, This strategy includes dimensions such as static type of service, time, user property, position and quasi real time/dynamic network load and matter Amount, user using multiple dimensions such as flow, these dimensions come trigger that ANDSF server sends to ANDSF APP client can be with The prompt switched over, and communicated between ANDSF server and ANDSF APP client and use the content that 3GPP standard defines, Push is ANDSF MO (management object), has reference format, the wlan network that ANDI mainly can choose UE at this time arranges Table or LTE network list give ANDSF APP client from ANDSF server push.ISMP is then to specify whether to cut It changes in these networks and when can be handed over.IARP, which then defines the i.e. business routing of which APN, can be switched to these In network and when can be handed over.

Fig. 5 B shows the ANDI policy information child node schematic diagram of one embodiment of the invention.Fig. 5 C shows the present invention one The ISMP policy information child node schematic diagram of embodiment.

In one embodiment, inter-system mobility strategy (ISMP) specifies whether to allow the movement between carry out system, and EPC system, which is linked into, for user selects most suitable access system.The strategy can be supplied to UE, and ANDSF can also be based on fortune Battalion's quotient's strategy modifies to the mobility strategy between system based on the UE network discovery sent and selection information.Work as terminal When can not enter EPC by multiple access connection, ISMP strategy is used.ISMP can identity user using which kind of access technology or which A specific access net access EPC, also can identify when to allow or forbids moving between system.Such as: ISMP can indicate not permit Perhaps it is switched to WLAN (or forbidding inter-system mobility under specific time or place scene) from LTE, can also indicate that WiMAX (Worldwide Interoperability for Microwave Access, worldwide interoperability for microwave accesses) access priority It is higher than higher than SSID1 in WLAN and wlan network (Service Set Identifier, service set) access priority SSID2 etc..When use automatically accesses net selection function, UE will not initiate EPC connection by restricted access net into ISMP, use If family selects by hand, without considering such limitation.Meanwhile ISMP is not also related to circuit domain business.When use automatically accesses net When network selects, when shift strategy indicates access EPC between system, if the access network or access technology type of operator's preference List of the list prior to user preference.

The present embodiment briefly explains lower access network discovery information (ANDI).According to the request of UE, ANDSF can provide UE The access network list of all access systems of adjacent domain.Access network information may include access technology type (such as WLAN Or WiMAX), Radio Access Network identifier (SSID of WLAN), other particular technique information such as one or more carrier frequency, The access network information when constraint condition such as condition identity provides is effective.Terminal can retain the previous ANDI received, directly New ANDI is pushed to system.

The present embodiment briefly explains routing policy (IARP) between lower APN.In order to support IP interface in OPIIS research topic Selection strategy, business of having formulated flow to the selection strategy of APN, introduce a new routing policy IARP (Inter-APN Routing Policies), selected APN must be currently with the presence of corresponding PDN connection.It each can be used as routing policy choosing The IP interface selected is necessarily connected to different APN.IARP connects the selection of identical APN by multiple IP interfaces are not included, and IP interface does not have corresponding APN to be not included in the routing decision of IARP yet.Meanwhile but existing APN selection mechanism for example Binding and user preference of a certain application with APN are all higher than IARP priority, and IARP is provided by H-ANDSF, if V-ANDSF It issues, UE can ignore this IARP.

ANDSF is the discovery that the discovery for realizing ANDSF by DNS or DHCP mode under non-roaming scene, it is also possible to The IP address of ANDSF is pre-configured in UE.Under roaming scence, UE with may obtaining the IP of H-ANDSF and V-ANDSF simultaneously Location.When UE is located under Visited PLMN (Public Land Mobile Network, public land mobile network), UE can make The IP address of ANDSF is obtained with dns resolution mode.The DNS mode that Fig. 6 shows one embodiment of the invention carries out ANDSF discovery Flow diagram.As shown in fig. 6, UE establishes connection by WLAN/CDMA/LTE and DNS, ANDSF, DNS mode carries out ANDSF It was found that process include:

Step 601, shift strategy between UE prefabrication system, UE send DNS (Domain Name System, domain name system to DNS System) query (inquiry).

Step 602, DNS inquires response (DNS query response).

Step 603, UE sends generic alert (generic alert) to ANDSF server.

Fig. 7 shows the flow diagram that message transport occurs between the ANDSF Server and UE of one embodiment of the invention. After UE completes ANDSF discovery procedure, by the strategy of triggering ANDSF, such as: the policy informations such as ANDI, ISMP are in ANDSF It is transferred between Server and UE.As shown in fig. 7, this method comprises:

Step 701, policy control and charging (PCC) or perception analysis system carry out updating network state.

Step 702, ANDSF server executes updating network state confirmation.

Step 703, ANDSF server sends SMS (Short Message Service, SMS (Short Message Service)) and arrives UE.

Step 704, Alert:Replace (end message).If not setting up secure connection, using transmission warning message: Replacement.

Step 705, which policy information ANDSF server pushes according to judgements such as position, application and network states.

Step 706, ANDSF server sends Status (state) to UE: Replace (replacement) policy information.

Step 707, UE sends condition responsive information to ANDSF server.

Step 708, UE assessment strategy executes the network selection of response.

Fig. 8 shows the hand-off process flow diagram of LTE to the WLAN of one embodiment of the invention, as shown in figure 8, this is cut Change of current journey includes:

Step 801, UE is accessed from LTE network, and PMIPv6 (Proxy Mobile IPv6, generation are used on S5/S8 interface Manage mobile IPv 6 protocol) or GTP tunnel, which is a kind of network-based regional mobility management protocol；

Step 802, access information interaction is carried out between ANDSF client and server, if user's selection executes switching, is taken Business device will be collected into the information (such as: IMSI, APN, IP address) of user, if user's selection does not execute switching, will continue It is resident on an LTE network；

Step 803, switching instruction and user information etc. are handed down to 3GPP AAA by newly-increased interface by ANDSF server；

Step 804, UE executes switching, will execute the access procedure by defined non-3 gpp, UE access WLAN is simultaneously initiated EAP (Extensible Authentication Protocol, Extensible Authentication Protocol) authentication process, 3GPP AAA are based on user Type of attachment is changed to " handover " by IMSI to insertion switching instruction in TWAG authorization messages, subsequent for by switching flow Definition is handled；

Step 805, TWAG gives P-GW to P-GW transmission Create Session Request message (including switching instruction), RAT type is identified as WLAN access.Then P-GW reassigns identical IP address according to switching instruction；

Step 806, oneself mark and APN information are passed to 3GPP aaa server by P-GW, and from 3GPP AAA Obtain authentication information；

Step 807, P-GW gives TWAN response Create Session Response, and connects before carrying the UE in LTE The IP address of fashionable distribution；

Step 808, the GTP tunnel between TWAG and P-GW is successfully established；

Step 809, TWAG notifies the foundation in the tunnel 3GPP AAA, EAP (Extensible Authentication Protocol, Extensible Authentication Protocol) process terminate i.e. the side WLAN connection establish complete；

Step 810, P-GW initiates the PDN connection in network and deactivates process, discharges the resource of LTE network side.

The inter-network switch method of the embodiment of the present invention, in the switching flow from LTE to WLAN: UE is in access wlan system Initialization access request is first carried out in the process, will be inserted into TWAG authorization messages based on user IMSI in 3GPP AAA network element Switching instruction, type of attachment is changed to " handover ", and subsequent TWAG will complete flow processing by the definition of switching flow, can be with Guarantee the seamless switching for only supporting the terminal of transparent single connection mode to can be realized LTE and wlan network under existing process, It ensure that the business continuance of requirement of real-time height application, and introduce APP ad hoc mode and realize user and across a network is cut The dominance changed.

Fig. 9 shows the hand-off process flow diagram of WLAN to the LTE of one embodiment of the invention.As shown in figure 9, the stream Journey includes:

Step 901, UE accesses EPC by WLAN, and GTP is used on S2a interface；

Step 902, information exchange is carried out between ANDSF client and server, if user's selection executes switching, server It will be collected into the current information of user (IMSI, APN, IP address etc.), if user's selection does not execute switching, will continue to be resident On an LTE network；

Step 903, switching instruction and user information etc. are issued MME by newly-increased interface by ANDSF server；

Step 904, UE executes switching, and UE sends Attach Request to MME, and MME is based on user IMSI insertion switching Instruction, request type is changed to " handover ", subsequent to be handled to define by switching flow:

Step 905, UE is connected to HSS by MME and is authenticated；

Step 906, MME execution position updates and subscription data acquisition process after authenticating successfully；

Step 907~step 908, MME selection SGW and P-GW, transmission Create Session Request (including switching Instruction) message to SGW arrives P-GW again.Because indicating comprising incision, tunnel is not switched to LTE from WLAN at this time by P-GW；

Step 909~step 910, P-GW respond Create Session Response message and arrive MME, message again to SGW In comprising UE access the IP address that uses in WLAN, instruction S5 carrying is established and is updated successfully, PMIPv6 (Proxy Mobile IPv6) or GTP tunnel is established；

Step 911, LTE is wireless and access bearer is established；

Step 912~913, MME sends modification carrying request (Modify Bearer Request) message and arrives again to SGW P-GW, modification carrying request include switching instruction.Tunnel is switched to the side LTE from WLAN because including switching instruction P-GW, is stood Carve the default for starting to establish message routing to SGW and dedicated EPS carrying.

Step 914~step 915, P-GW return to modification carrying response (Modify Bearer to SGW and MME Response) confirmed；

Step 916, LTE system connection, which is established, completes, and user carries out sending and receiving for data using LTE；

Step 917, the resource that P-GW initiates the side WLAN discharges process.

The inter-network switch method of the embodiment of the present invention, in the switching flow from WLAN to LTE, UE is in access LTE system The Attach Request for first carrying out " initial attachment " in the process will switch instruction based on user IMSI insertion in MME network element, will Type of attachment is changed to " handover ", and subsequent MME will complete flow processing by the definition of switching flow, it is ensured that existing It only supports the terminal of transparent single connection mode to can be realized the seamless switching of LTE and wlan network under process, ensure that real-time It is required that the business continuance of high application, and introduces APP ad hoc mode and realize the dominance that user switches across a network.

Figure 10 shows the structural schematic diagram of the network element of one embodiment of the invention, and the network element can be in one embodiment ANDSF server.As shown in Figure 10, which includes:

Sending module 1003, for sending across a network switch prompting to the ANDSF client of user equipment (UE) according to strategy；

Receiving module 1001, for receiving switching command and user information from UE；

Processing module 1002 is used to generate switching instruction according to switching command and user information, passes through sending module 1003 Target network is sent by switching instruction；

Sending module 1003 is also used to that UE is notified to execute across a network switching so that UE is switched to target network.

In one embodiment, user information includes international mobile subscriber identity IMSI, access point name APN, network association IP address is discussed,

Sending module 1003 is used for, and sends the control that target network is arrived in switching instruction according to switching command and user information Device, to trigger the connection that packet data gateway P-GW establishes UE and target network based on IP address；And/or strategy is when including Between, position, wlan network load and quality, LTE network load and quality or use application type.

Figure 11 shows the structural schematic diagram of the across a network switching system of one embodiment of the invention, as shown in figure 11, the net Member includes:

Such as above-mentioned network element 1101；ANDSF client 1102 switches for receiving network element according to the across a network that strategy is sent Prompt sends switching command and user information to network element；P-GW1103 judges whether it is UE points for receiving switching instruction Matched IP address, if distributing IP address, the connection of UE and target network is established using identical IP address；Third generation cooperation Partnership Program verifying, authorization and accounting 3GPP AAA 1104, for controlling UE access WLAN；Controller is mobile management entity MME1105, for controlling UE access LTE.

In one embodiment, UE is switched to WLAN WLAN from long term evolution LTE, comprising: network element 1101 is used for will Switching instruction including user information is sent to 3GPP AAA；3GPP AAA 1104 is used to execute switching access WLAN simultaneously in UE When initiating Extensible Authentication Protocol authentication process, the insertion switching instruction in the authorization messages to TWAG based on user IMSI will be attached Type be changed to switching request；After P-GW 1103 is used to receive the session establishment request that TWAG is sent according to switching request, for UE Distribute identical IP address；P-GW 1103 is used to its own P-GW mark and APN information passing to 3GPP AAA service Device obtains authentication information from 3GPP AAA；P-GW 1103 is sent to UE for sending session establishment response, by IP address, IP Location is the IP address that UE is used in LTE access.

In one embodiment, UE is switched to long term evolution LTE from WLAN WLAN, comprising: network element 1101 is used for will Switching instruction and user information are issued to MME；MME1105 is used to receive the IMSI insertion based on user after the attach request of UE Switching instruction, is changed to switching request for attach request；MME1105 is for authenticating UE according to HSS, if authenticating successfully, MME Execution position updates and subscription data acquisition process；P-GW1103 is used to send session establishment request transmission session according to MME and builds Response is stood, includes that UE accesses the IP address used in WLAN in session establishment response.

Description of the invention is given for the purpose of illustration and description, and is not exhaustively or will be of the invention It is limited to disclosed form.Many modifications and variations are obvious for the ordinary skill in the art.It selects and retouches It states embodiment and is to more preferably illustrate the principle of the present invention and practical application, and those skilled in the art is enable to manage The solution present invention is to design various embodiments suitable for specific applications with various modifications.

Claims (10)

1. a kind of inter-network switch method characterized by comprising

Access network discovery and selection function ANDSF server according to strategy to the ANDSF client of user equipment (UE) send across Network switching prompt, wherein the ability of the UE is transparent single connection mode, and transparent single connection mode does not support transmitting APN letter Breath, packet data network gateway PDN type information；

ANDSF server receives switching command and user information from the UE, wherein the user information includes the world Mobile identification number IMSI, access point name APN, network protocol IP address；

ANDSF server sends switching instruction according to the switching command and user information and arrives target network, comprising: ANDSF Server issues the controller that target network is arrived in switching instruction by the interface of the controller with target network, by target network Controller insertion switching instruction during user establishes connection to switching target network, to trigger packet data gateway P- GW establishes the connection of the UE Yu the target network based on the IP address, wherein the controller of target network is moving tube Manage entity MME or third generation partner program verifying, authorization and accounting 3GPP AAA；

ANDSF server notifies the UE to execute across a network switching so that the UE is switched to the target network.

2. the method according to claim 1, wherein P-GW, which is based on the IP address, establishes the UE and the mesh Mark network connection include:

The P-GW receives switching instruction, judges whether it is the UE and distributed IP address, if distributing IP address, uses phase Same IP address establishes the connection of the UE and target network.

3. method according to claim 1 or 2, which is characterized in that UE is switched to WLAN from long term evolution LTE When WLAN, the controller be third generation partner program verifying, authorization and accounting 3GPP AAA, ANDSF server according to The switching command and user information send switching instruction and are based on the IP to the controller of target network, to trigger P-GW The connection that the UE and the target network are established in address includes:

Switching instruction including the user information is sent to 3GPP AAA by ANDSF server；

3GPP AAA is being given when UE executes switching access WLAN and initiates Extensible Authentication Protocol authentication process based on user IMSI Insertion switching instruction, is changed to switching request for type of attachment in the authorization messages of credit WLAN access gateway TWAG；

After P-GW reception TWAG is requested according to the session establishment that the switching request is sent, with distributing identical IP for the UE Location；

Its own P-GW mark and APN information are passed to 3GPP aaa server by P-GW, obtain authentication letter from 3GPP AAA Breath；

P-GW sends session establishment response, the IP address is sent to the UE, the IP address is that UE makes in LTE access IP address.

4. method according to claim 1 or 2, which is characterized in that UE is switched to long term evolution from WLAN WLAN When LTE, the controller is mobile management entity MME, and the ANDSF server is according to the switching command and user information It sends switching instruction and establishes the UE and the target to the controller of target network, to trigger P-GW based on the IP address The connection of network includes:

Switching instruction and user information are issued to MME by ANDSF server；

MME receives the IMSI insertion switching instruction based on user after the attach request of UE, and the attach request is changed to switch Request；

MME authenticates UE according to HSS, if authenticating successfully, MME execution position updates and subscription data acquisition process；

P-GW sends session establishment request according to MME and sends session establishment response, includes that UE exists in the session establishment response WLAN accesses the IP address used.

5. the method according to claim 1, wherein including:

The strategy is including time, position, wlan network load and quality, LTE network load and quality or uses application type.

6. a kind of network element characterized by comprising

Sending module, for sending across a network switch prompting to the ANDSF client of user equipment (UE) according to strategy, wherein institute The ability for stating UE is transparent single connection mode, and transparent single connection mode does not support transmitting APN information, packet data network gateway PDN Type information；

Receiving module, for receiving switching command and user information from the UE, wherein the user information includes state Border mobile identification number IMSI, access point name APN, network protocol IP address；

Processing module will by the sending module for generating switching instruction according to the switching command and user information Switching instruction is sent to target network；

The sending module is also used to notify that the UE executes across a network switching so that the UE is switched to the target network, with And the controller for switching instruction and arriving target network is issued by the interface of the controller with target network, so as to by target network Controller insertion switching instruction during user establishes connection to switching target network, to trigger packet data gateway P- GW establishes the connection of the UE Yu the target network based on the IP address, wherein the controller of target network is moving tube Manage entity MME or third generation partner program verifying, authorization and accounting 3GPP AAA.

7. network element according to claim 6, which is characterized in that

The strategy is including time, position, wlan network load and quality, LTE network load and quality or uses application type.

8. a kind of across a network switching system characterized by comprising

Network element as claimed in claims 6 or 7；

ANDSF client, for receive the network element according to strategy send across a network switch prompting, send switching command and User information is to the network element；

P-GW judges whether it is UE and distributed IP address, if distributing IP address, using identical for receiving switching instruction IP address establish the connection of the UE and target network；

Third generation partner program verifying, authorization and accounting 3GPP AAA, for controlling UE access WLAN；

Controller is mobile management entity MME, for controlling UE access LTE.

9. system according to claim 8, which is characterized in that UE is switched to WLAN WLAN from long term evolution LTE, Include:

The network element is used to the switching instruction including the user information being sent to 3GPP AAA；

3GPP AAA is used to be based on user IMSI when UE executes switching access WLAN and initiates Extensible Authentication Protocol authentication process Insertion switching instruction, is changed to switching request for type of attachment in the authorization messages to TWAG；

P-GW is used to receive after the session establishment that credit WLAN access gateway TWAG is sent according to the switching request requests, for institute It states UE and distributes identical IP address；

P-GW is used to its own P-GW mark and APN information passing to 3GPP aaa server, obtains and reflects from 3GPP AAA Weigh information；

P-GW is sent to the UE for sending session establishment response, by the IP address, and the IP address is that UE is accessed in LTE When the IP address that uses.

10. system according to claim 8, which is characterized in that UE is switched to long term evolution from WLAN WLAN LTE, comprising:

Network element is issued to MME for that will switch instruction and user information；

MME is used to receive the IMSI insertion switching instruction based on user after the attach request of UE, and the attach request is changed to Switching request；

MME is for authenticating UE according to HSS, if authenticating successfully, MME execution position updates and subscription data acquisition process；

P-GW is used to send session establishment request according to MME and sends session establishment response, includes UE in the session establishment response The IP address used is accessed in WLAN.