CN101242655B

CN101242655B - A method for selecting media routing mode in home network under roaming status

Info

Publication number: CN101242655B
Application number: CN2008100083742A
Authority: CN
Inventors: 李志军; 郝振武; 芮通
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2008-03-04
Filing date: 2008-03-04
Publication date: 2012-06-13
Anticipated expiration: 2028-03-04
Also published as: CN101242655A

Abstract

A media route mode selecting method for home network under roaming, which includes steps of: PCRF of visited network sends access information of the UE to access visited network to PCRF of home network when UE establishes IP carrier, or IP carrier of visited network is changed or canceled, PCRF stores the information; PCRF of the home network sends the mentioned information to P-CSCF of home network who provides service the UE; when calling starting request from the UE or calling ending request to the UE is received, P-CSCF or S-CSCF of the home network select media route mode for the UE based on the mentioned access information. Applying the inventive method into IMS access network, the problem that IMS home network can not know whether the UE supports local rolling out schema can be effectively solved when UE roams to visiting network, and further can select optimized media route mode for the UE.

Description

A kind of home network under roaming status is selected the method for media routing mode

Technical field

The present invention relates to the communications field; Relate in particular under a kind of roaming condition; IP (Internet Protocol; Internet Protocol) method of IP multimedia subsystem, IMS (IP Multimedia Core Network Subsystem is called for short IMS) selecting media routing mode in home network (this locality is produced or the home network route pattern).

Background technology

IMS is the core of communication network of new generation, and its distinguishing feature is to have adopted Session initiation Protocol (Session Initiation Protocol is called for short SIP) system; Communication is irrelevant with access, can possess multiple media business controlled function and separate with bearing capacity, calls out and separates with session; Application separates with service; Business and network detach, and multiple abilities such as mobile network and internet service fusion, the trend of communication network fusion development has been complied with in the proposition of IMS.

Fig. 1 shows network element entity and annexation thereof relevant with the present invention in the IMS architecture.Wherein:

The terminal equipment that subscriber equipment (User Equipment is called for short UE) 101 representative of consumer are used;

CSCF (Call Session Control Function; Be called for short CSCF) be the core network element of control conversation procedure; Comprise: Proxy Call Session Control Function (Proxy-CSCF; Be called for short P-CSCF) 102, query call conversation control function (Interrogating-CSCF is called for short I-CSCF) 103, service call conversation control function (Serving-CSCF is called for short S-CSCF) 104;

Home subscriber server (Home Subscriber Server is called for short HSS) the 105th, the main storage server of all data relevant among the IMS with user and server;

Application server (Application Server is called for short AS) 106 provides the network element of increment multimedia service.

Between each network element illustrated in fig. 1, UE links to each other with P-CSCF through Gm; Realize interconnection through Mw between P-CSCF, I-CSCF, S-CSCF; HSS links to each other with I-CSCF, S-CSCF through the Cx interface realization, realizes linking to each other with AS through Sh interface; S-CSCF realizes linking to each other with AS through ISC (IMS servicecontrol, the professional control of IMS) interface.

In 3GPP (3rd Generation Partnership Project, third generation partner program) standard, signaling and operation flow are controlled by the network element entity that with CSCF is core; And the policy control of media bearer and charging etc. are then carried out by policy charging control system (Policy Charging Control is called for short PCC).

Fig. 2 shows each main network element entity and annexation thereof under the PCC framework of 3GPP standard R7 version.Wherein:

Subscribe to configuration store (Subscription Profile Repository is called for short SPR) 201 and be used to store user's strategy and charging configuration information;

Applied layer interface function (Application Function is called for short AF) the 202nd, the general designation of the network element entity that the business of realization is controlled;

"Policy and Charging Rules Function (Policy and Charging Rules Function, be called for short PCRF) the 203rd, the essential functional entities of PCC framework is used for obtaining, assemble, issue etc. of control strategy and charging regulation;

Strategy and charge execution function (Policy and Charging Enforcement Function is called for short PCEF) the 204th, concrete strategy and the execution of charging point are usually located in the gateway (GateWay is called for short GW);

Online Charging System (Online Charging System is called for short OCS) 205 provides online billing function;

Off-line accounting system (Offline Charging System is called for short OFCS) 206 provides the offline charging function.

In PCC framework shown in Figure 2, SPR has stored user's the strategy and the configuration information of charging; PCRF utilizes the Sp interface from SPR, to obtain user's the strategy and the relevant configuration information that charges, and is assembled into the PCC rule, utilizes the Gx interface to be issued to PCEF.PCEF use Gx interface is regular to PCRF request PCC, and utilizes the PCC rule that the Media Stream through GW is verified, what control and restricting media flowed passes through.If there is OCS, then PCEF asks charge informations such as media authorization, report medium flow through the Gy interface to OCS.If there is OFCS, then PCEF reports charge information through the Gz interface to OFCS.

Under the common roaming scence, after UE roams into the visit net, set up IP at visit net network and carry, find the P-CSCF of visit net, utilize this P-CSCF to be registered to the IMS home network.But, under this roaming scence, can require UE to carry out re-registration process usually at the visit net, for the UE that is conversing, can cause service disruption then unavoidablely.

Now, frequent situation about switching is more and more between roaming network, and for not break in service when roaming is switched, the 3GPP tissue has proposed to utilize mobile IP technology to realize roaming, solves mobility management method.Its thought is exactly, when UE registers in the IMS home network, for it distributes IP address, P-CSCF, the S-CSCF of home network; After UE roams into the visit net, adopt mobile IP technology, still using home network is its IP address allocated, to keep the continuity of signaling aspect, need not to register again, switch session.On bottom carried, the Care-of Address of mobile IP technology use visit net, tunneling technique etc. guaranteed that UE under roaming scence, can in time notify home network current physical location.

But mobile IP technology is applied to roaming scence also has its weak point.Fig. 3 A is the roaming scence sketch map that adopts mobile IP technology.Shown in Fig. 3 A,, use the home network IP address allocated, and in fact UE is currently located at the visit net because UE signaling aspect and medium aspect all adopt mobile IP technology.Therefore according to the needs of route, all mail to the Media Stream of UE, all need send to home network earlier, on the IP gateway of home network, send to the Care-of Address of UE at the visit net through the tunnel, are transmitted to UE at the visit net then.

That is to say, adopt under the scene that moves IP, exist the situation that a large amount of medium routes travels back across home network.Under the situation that more prevalent, the professional required bandwidth of roaming promotes day by day, media content is more and more abundanter, the medium route travels back across home network will cause a large amount of wastings of resources, and when having wasted bandwidth, also waste the network processes time.

In order to solve the medium route detour problem that exists under the roaming scence that adopts mobile IP technology, the 3GPP tissue has proposed a kind of solution shown in Fig. 3 B.In this scene, after UE adopts mobile IP technology to roam into the visit net, distribute visit net IP address a: IP-L by the visit net for it, and serve for it by a visit net IP gateway.This solution adopts signaling paths through home network, and media path is directly netted the method that IP gateway produces from visit, avoids the alternate route of medium.

The method of this solution medium alternate route shown in Fig. 3 B is referred to as this locality by 3GPP and produces (Local Breakout is called for short LBO).Be after UE roams into the visit net; UE holds the home network IP address allocated; And the maintenance signaling paths, visit net simultaneously and distributed an IP address that can be used for the medium communication again, so UE can use home network IP address allocated and signaling paths to carry out the signaling transmission; And adopt visit net IP address allocated to carry out media delivery, realize signaling and medium separating on different paths.

Produce pattern (LBO pattern) with respect to this locality of medium, do not select this locality to produce the medium route, and route is returned home network,, be referred to as the home network route pattern (Home Routed is called for short the HR pattern) of medium route through the pattern of home network transfer.

At present, the 3GPP normal structure promotes to the efficiency optimization under the roaming scence, speed in the System Architecture Evolution research of (System Architecture Evolution is called for short SAE), has proposed a series of framework and imagination.Wherein, for the affirmation of LBO pattern under the roaming scence, key exactly in order to deal with problems.

To the roaming scence shown in Fig. 3 A～3B, in conjunction with the existing research of SAE, the 3GPP tissue provides the architectural framework of some references, shown in Fig. 4 A～4C.This framework has mainly been described as UE and has been registered to home network, roam into the visit net simultaneously after, the coordination of the strategy between coordination on signaling paths and the media path between each network element and home network and the visit net and the control of chargeing etc.

In the frame of reference shown in Fig. 4 A; There is Packet Data Network's IAD (Home network PDN Gateway that is positioned at home network; Abbreviation H-PGW), Packet Data Network's IAD (Visited network PDN Gateway is called for short V-PGW) that is positioned at the visit net.H-PGW and V-PGW close as the grouped data access network of home network and visit net respectively, have simultaneously like the IP gateway function described in Fig. 3.Simultaneously, in the visit net, there is PCRF (the Visitednetwork PCRF of a visit net; Be called for short V-PCRF), the PCRF of V-PCRF and home network (Home networkPCRF is called for short H-PCRF) sets up effectively contact; V-PCRF is as the concrete execution agency of H-PCRF; H-PCRF is as strategy and the metering data supplier of V-PCRF, and both coordinate each other, controls the purpose of visit net Media Stream according to home network strategy and charging configuration information to reach the visit net.

In this frame of reference, the gateway of user media face is positioned at the visit net, and the gateway of subscriber signaling face is positioned at home network; The visit net need be realized jointly controlling of signaling and media bearer through the co-ordination with home network.Simultaneously, in this frame of reference, the P-CSCF of IMS home network is known ordered Media Stream incident as the access point and the V-PCRF exchange of IMS network application function part.

Fig. 4 A typically both can adopt the home network route pattern, also can adopt this locality to produce the scene of pattern.In addition, also exist the PDN GW that has only shown in Fig. 4 B to be positioned at home network, and the scene of having only a PDN GW to net in visit shown in Fig. 4 C.For the different application scene shown in Fig. 4 A, Fig. 4 B, Fig. 4 C; The IMS home network all should be able to be discerned the media routing mode that current UE can adopt; The medium method for routing should be able to satisfy the needs of these scenes, makes system of selection operate as normal in above-mentioned scene of medium route.

When UE after IMS home network registration, roam into the visit net, after visit net network had been set up the IP that can supply the medium route and carried, there were two alternative paths in Media Stream, one is the home network route, one is that route is produced in visit net this locality.But, because the signaling paths that UE uses use is the IP address of home network, no matter be that UE initiates registration to home network, or UE makes a call, the IMS home network does not know that all UE can carry out the path that route is produced in this locality for medium one of visit net existence.That is to say; When UE made a call, the IMS home network can not use this locality of medium route to produce the path because know UE at the visit net, just can't realize that the IMS home network is selected and the medium routed path of control UE yet; Realize optimizing the medium Route Selection, avoid the circuitous purpose of medium route.

Same situation also appears in the following scene: UE nets start in visit, after having found and set up the IP carrying of home network and having visited the IP carrying of net, utilizes the IP carrying of the home network of having set up to be registered to the IMS home network.Wherein, UE sets up process that the IP of home network carries can be before the IP that sets up the visit net carries, also can after.

Produce for this locality of using the medium route, the IP that at first needs UE to set up the visit net at the visit net carries.Fig. 5 sets up the method flow diagram that IP carries at the visit net after visiting net for UE roams into.

The flow process that UE sets up the IP carrying of visiting net is following:

S501, the GW (PCEF) of visit net receives IP and carries the request of setting up, and distributes the IP address of a visit net for the user;

S502, the PCEF affirmation need be carried out the PCC authorization check, is that indication request is set up in V-PCRF transmission IP carrying to the PCRF of visit net, and request V-PCRF returns information such as the spendable service of user, PCC rule;

PCEF must comprise the IP address of sign, the UE of following key message: UE, the network identity that UE inserted (PLMN Identifier, PLMN sign) in the request that sends to V-PCRF, PDN Gateway sign (PDN Identifier), IP bearer types, IP that UE inserted carry and set up pattern, default charging way etc.

The sign of above-mentioned UE can be the UE sign of IP bearing bed, also can be the UE sign of IMS operation layer, like IMSI (Intemational Mobile Subscriber Identifier, international mobile subscriber identity).If the UE of IP bearing bed sign is different with the sign of the UE that the IMS operation layer provides, then PCRF need safeguard the mapping relations between these two kinds of signs.

Wherein, the IP address of the sign of UE and UE can be used to identify the IP carrying that belongs to a UE.

S503, V-PCRF detects the above-mentioned request that PCEF sends, and detecting this request is the request that needs home network to handle, and simultaneously, V-PCRF may do some decision-makings based on this locality configuration;

S504, V-PCRF sends request to the PCRF of home network (being H-PCRF), asks it to return information such as the admissible service of user, PCC rule;

S505, if there is not this user's relevant information on the H-PCRF, then H-PCRF sends request to SPR, with the strategy that obtains this user and the relevant configuration information that charges;

Send in the request of SPR at H-PCRF, can comprise following message usually: the PDN identification information of carrying etc. is set up in user's identification information, request.H-PCRF possibly require the information change situation of SPR notice H-PCRF about this user in this request.

S506, H-PCRF are kept at H-PRCF this locality with it after getting access to required configuration information from SPR;

At least comprise in the above-mentioned configuration information: admissible service, PCC rule.

S507, H-PCRF utilizes the configuration information that obtains from SPR, produces the strategic decision-making and the charging regulation of home network;

S508, H-PCRF return the strategic decision-making and the charging regulation information of above-mentioned home network to V-PCRF;

After S509, V-PCRF receive the strategic decision-making and charging regulation information of H-PCRF transmission, visit the local policy decision-making of net;

S510, V-PCRF sends to PCEF with strategic decision-making with during charging regulation is included in tactful and charging regulation gives information; In this message, comprise usually: selected IP carries the pattern of setting up, default charge mode; After GW (PCEF) receives information such as strategic decision-making and charging regulation, carry out this strategic decision-making;

S511, PCEF sends credit request to the online charging function (Proxy-OCS) of acting on behalf of of visit net, for it provides the relevant initialization input information that charges, with the charging credit of request to charging regulation;

Because if desired this user is carried out online charging, then have at least a PCC rule to be activated, so that PCEF can activate the online charging process.

S512 if online charging can be used, forwards the OCS of home network to before the request of Proxy-OCS with the PCEF transmission of visit net;

S513, if online charging can be used, then the OCS of home network is that PCEF prepares corresponding charging credit information, the OCS of home network is transferred to the charging credit information through the credit response message Proxy-OCS of visit net; May trigger re-authorization to each credit of chargeing simultaneously;

S514, if online charging can be used, the credit response message that comprises the charging credit information is transferred to GW (PCEF);

S515, final, at least one PCC rule is successfully activated.If the online charging function is activated, and OCS provides available charging credit, then GW (PCEF) notice media bearer successfully foundation.

In flow process shown in Figure 5,, need let the V-PCRF of visit net and the H-PCRF of home network set up effectively contact in order to let the visit net can control Media Stream.Use online charging if desired, then the online charging function of visit net must be served as the agency of the online charging function of home network.

After IP as shown in Figure 5 carried and sets up the flow process completion, correspondingly, a visit net IP who just exists for the UE distribution carried.The IP beared information that is used to identify a UE can comprise: the IP address of the sign of UE (Subscriber Identifier), UE.A UE possibly exist a plurality of IP to carry, and relies on these key messages, can distinguish which IP carrying and belong to which UE, and which IP carries which the IP address that belongs to UE.Further, based on the Access Network sign in the IP carrying attribute, can distinguish this IP carrying and be positioned at which access network.

Fig. 6 is that when being registered to the IMS system, P-CSCF and PCC carry out mutual method flow diagram after UE has set up the IP carrying.After this flow process was applied in the IP carrying of having set up home network, UE was to the process of IMS home network registration.

It should be explicitly made clear at this point that UE is to the process of IMS home network registration, might set up before the local IP of visit net carries, also possibly set up after visit net IP carries at UE at UE.

UE is following to the flow process of IMS network registry:

S601, UE are to the registration of IMS home network, and promptly UE sends the SIP register requirement to the P-CSCF of IMS home network;

Under scene described in the invention, the home network IP address that UE uses home network to distribute is that H-IP initiates registration;

After S602, P-CSCF receive the register requirement of UE, according to normal flow, with forwarding next node before the register requirement to;

S603, after having accomplished operation such as the authentication in the registration process, the IMS home network is sent 200OK message to P-CSCF, shows that the registration of UE is successful;

S604, P-CSCF gives UE with the 200OK forwards; After UE receives 200OK message, know registration success.

After succeeding in registration, the P-CSCF in the IMS home network, S-CSCF be last all to have stored some important informations that UE is linked into home network, as by the home network IP address allocated.These information will be used in the processing procedure of the calling of calling that the follow-up UE of receiving initiates or sensing UE.

S605; After UE succeeds in registration; P-CSCF sends authentication request (DiameterAA-Request is called for short AAR) to PCRF, requires PCRF that UE is carried out the inspection of medium authentication; The SIP session and the IP that distributes for UE that require PCRF will belong to the IMS session layer of UE simultaneously carry and bind; And SIP session and corresponding PCC rule bound, so that PCRF can be according to the requirement control bottom medium of SIP session, perhaps the Media Stream incident (like the bottom media break) with the IP bearing bed feeds back to the SIP session;

In order to carry out binding, P-CSCF comprises the IP address information of UE at least in the AAR request of sending to PCRF, and PCRF can bind according to the IP carrying that the IP address of UE is distributed with the SIP session with for UE.Extraly, P-CSCF also possibly provide the sign (under IMS, being often referred to the private user identity of UE) of UE to give PCRF, so that bind better.

The session information that relies on the IP bearing bed that these information that P-CSCF provided and PCRF self stored, the IP carrying that PCRF can distribute with the SIP session that belongs to UE with for UE is bound.

Simultaneously, in this step, do not carry for UE sets up corresponding IP if PCRF detects, just binding procedure can't be accomplished, then PCRF notice P-CSCF medium failed authentication;

After S606, PCRF receive the AAR request of P-CSCF, will belong to the SIP session of UE and the IP that distributes for UE carries and binds, the PCC rule of correspondence is bound with it simultaneously;

S607, bind successfully after, PCRF sends authentication response (DiameterAA-Answer is called for short AAA) to P-CSCF, confirms that medium authentication and binding session process accomplish;

S608; If previous PCRF does not subscribe to the Media Stream incident of IP bearing bed to PCEF, like medium foundation, medium change, media break etc., then PCRF sends re-authentication requests (Diameter Re-Auth-Request to PCEF; Be called for short RAR) order, to subscribe to such incident;

S609, PCEF confirm that PCRF subscribes to successfully the media event that belongs to this UE, send discrimination weight response (Diameter Re-Auth-Answer is called for short RAA) message to PCRF.

After process shown in Figure 6 is accomplished, the effective binding of IP carrying having carried out that PCRF will belong to the SIP session of UE and distribute for UE.

That is to say that under scene described in the invention, PCRF carries the IP of the home network of the SIP session of the home network of UE and UE successfully and binds.The key message of binding has: the IP address of UE, and the ID (under the IMS system, can be IMSI) that is used for the auxiliary UE that binds.

But, be that the IP that this UE distributes carries, the IP that distributes except home network carries, also have one to set up by the visit net, this visit net IP carries not to be had and the SIP session of UE is bound.

Flow chart shown in Figure 7 has been described under roaming scence of the present invention, and UE makes a call, and the IMS home network can't realize the situation of medium Route Selection because lack necessary information.

UE adopts mobile IP technology to roam into the visit net, and the visit net has also distributed the path that can supply medium this locality to produce for UE.At this moment, IP address allocated makes a call if UE uses home network institute, and in the case, home network can't adopt the medium routing optimality to this situation, promptly can't require medium to produce from visit net this locality.

S701, UE initiates a call request, and this call request is sent on the P-CSCF; Comprise media negotiation information in this call request;

In this call request, what UE used is that home network is its IP address allocated, and the SDP that wherein comprises (Session Description Protocol, Session Description Protocol) data are used to consult link information and media formats.And UE is used to consult the medium route in the SDP data address also is that home network is its IP address allocated.

After S702, P-CSCF receive the call request of UE, therefrom extract and detect descending link information, comprising: call initiator (UE) is used for carrying out information such as the IP address, port of medium conversation;

S703, P-CSCF is transmitted to call request by the network of exhaling eventually, wherein comprises the media negotiation information of call initiator;

S704 is accomplished media negotiation by the whole side of exhaling, and returns the media negotiation result; Comprising the media information of acceptable call initiator, and we the media information that can provide;

S705, P-CSCF extracts and detect up link information from the media negotiation result who receives, comprising: the side of exhaling is used for carrying out the information such as IP address, port of medium conversation eventually;

S706, P-CSCF asks media authorization to PCRF.In this request, P-CSCF is up link information, descending link information, and other necessary information offers PCRF, carries out authorization check for the PCRF medium, so as can implementation strategy control, operation such as media resource reservation;

S707, PCRF store the session information of SIP layer in this locality, and the session of these information and IP bearing bed is associated;

S708, PCRF sends the media authorization response to P-CSCF, and expression is authorized successful, can carry out operations such as policy control, resource reservation;

S709, P-CSCF notification call initiator (UE) media negotiation is accomplished; UE needs to adopt the IP address of appointment and port to send Media Stream according to the result of media negotiation;

S710, PCRF are according to the SIP layer conversation link information of obtaining from P-CSCF, and strategy and charging decision information, accomplish policy control and resource allocation process alternately with PCEF.

S711, UE, P-CSCF etc. accomplish the subsequent session handling process.In flow, the medium of call initiator are mail in the side of exhaling eventually, must travel back across home network.

In the media authorization request of the step 706 of above-mentioned flow process; P-CSCF provides necessary SIP session information; So that PCRF can carry session information with this SIP session and the IP that has set up binding before and associate, and further whether inspection allows processes such as medium pass through, implementation strategy control.The important information that P-CSCF provided comprises: the session identification information of the link information of call initiator and calling receiver (like IP address, port), SIP session etc.

Because in call flow shown in Figure 7, the employed signaling of UE address and the media address that is used for media negotiation are the home network IP address allocated; Therefore after session was set up, the medium route need travel back across home network.Under this scene; Because home network only knows that UE is linked into the information of home network; Can't know that UE is linked into the information of visit net, can't know that therefore the current this locality of medium route of can using of UE produces pattern, more can not require UE to adopt this locality to produce pattern to optimize the medium route; That is to say, can't carry out the medium Route Selection.

After visit net IP shown in Figure 5 carried foundation, UE just possibly adopt visit net this locality of medium route to produce pattern.But under this roaming scence, the IMS home network only can know that UE has set up the signaling and the media bearer path of a home network, and does not know that there is an other path that can supply medium route this locality to produce in UE at the visit net.That is to say that the IMS home network thinks that UE only can use the media bearer path of home network foundation, and the media bearer path that can not select and use other.

Actual conditions are; UE has been assigned with the medium routed path of operable optimization at the visit net; For the IMS home network, need know at first that UE can use medium route this locality to produce at the visit net, select then an optimization, without prejudice to the media routing mode of other decision factor.

Can find that from above analysis under roaming scence, IMS to reduce the unnecessary wasting of resources, at first need know that the UE that is arranged in the visit net can use this locality of medium route to produce pattern for the employed media routing mode of UE of can making a strategic decision.Be in the prior art, the IMS home network lacks a kind of method and obtains the access information of UE at the visit net, like Access Network sign, IAD sign, visit net IP address etc.These information only upward exist at the GW (PCEF) of visit net and the V-PCRF of visit net, and the IMS home network is not also known, should adopt any medium routing mode in the calling procedure of therefore can't further making a strategic decision.

Have only when IMS through someway, known that UE is linked into the access information of visit net after, can know that just UE can use this locality of medium route to produce pattern.Just can be further based on the local policy or the customer service configuration of IMS home network, whether decision forces UE to use certain specific media routing mode, produces pattern like this locality, and makes UE adjust media routing mode as indicated.

At present, in the 3GPP tissue, insert down for the IMS system, how the IMS home network knows that the UE that is positioned at the visit net can adopt this locality to produce pattern, and further does the medium Route Selection, does not also have corresponding solution.

Summary of the invention

The technical problem that the present invention will solve provides a kind of medium route selection method; Home network can't be known the access information of the subscriber equipment that is arranged in the visit net in the solution prior art; Therefore can't know that the current this locality of medium route of can using of UE produces pattern, can't carry out the problem of medium Route Selection.

In order to address the above problem, the present invention provides a kind of home network under roaming status to select the method for media routing mode, and this method comprises the steps:

Set up that visit net IP carries or visit net IP carries and changes or when nullifying at UE, the access information that the PCRF of visit net inserts the visit net with this UE sends to the PCRF of home network, and the PCRF of home network preserves this information;

The PCRF of home network sends to above-mentioned access information the P-CSCF that the home network of service is provided for this UE;

Call for and ask or when pointing to the final call request of this UE, the P-CSCF of home network or S-CSCF are this UE selection media routing mode according to above-mentioned access information receiving rising of this UE.

In addition, set up that visit net IP carries or visit net IP carries and changes or when nullifying at UE, the access information that the PCRF of visit net inserts the visit net with said UE is included in the PCRF that sends to home network in strategy and the charging regulation message of request home network.

In addition, the access information that said UE inserts the visit net comprises sign and following one or more the combination of UE: the Access Network sign of said visit net, and the IAD sign of said visit net, UE is linked into the IP address of visit net.

In addition, initiate registration to home network, after the PCRF of home network receives the authentication request of said P-CSCF transmission, insert the access information that visit is netted, then it is included in the authentication response and sends to said P-CSCF if this locality stores said UE at UE.

In addition, initiate registration to home network, after the PCRF of home network receives the authentication request of said P-CSCF transmission, preserve the incidence relation of said P-CSCF and UE at UE;

Set up that the IP carrying of visit net or visit net IP carrying change or when nullifying at UE; The PCRF of visit net inserts the PCRF that the access information of visiting net sends to home network with this UE, and the PCRF of home network sends to this P-CSCF based on the incidence relation of above-mentioned P-CSCF and UE with above-mentioned access information.

In addition, the sign that comprises said UE in the said authentication request; Said UE inserts the sign that comprises UE in the access information of visiting net;

The PCRF of said home network inserts the access information that visit is netted according to local this UE that whether preserves of the sign inquiry of UE.

In addition, if local preserve the access information that this UE inserts the visit net, after the PCRF of said home network receives said authentication request, the sign of using UE with the home network IP of UE carry with the visit of UE net loaded carry out related.

In addition, the PCRF of said home network also is included in said authentication response with the access information of home network and sends to said P-CSCF.

In addition; Call for and ask or when pointing to the final call request of this UE receiving rising of said UE; Said P-CSCF or S-CSCF carry out the route pattern decision-making according to the access information that said UE inserts the visit net, judge that the current this locality of medium route of whether can using of this UE produces pattern;

If pattern is produced in the current this locality of medium route of can using of this UE, then P-CSCF or S-CSCF are the selected media routing mode of this UE according to customer service configuration and/or local policy;

Said media routing mode comprises: pattern is produced in this locality, the home network route pattern.

In addition; Call for and ask or when pointing to the final call request of this UE receiving rising of said UE; If the current use of said UE is not that said S-CSCF or P-CSCF are its selected media routing mode, then S-CSCF or P-CSCF will notify to this UE for its selected media routing mode through send message to UE.

In addition, call for and ask receiving rising of said UE, said S-CSCF or P-CSCF through 380 message that medium route indication information is carried in transmission, notify that this UE is said to be its media routing mode of selecting in the process of carrying out media negotiation;

When receiving the final call request of pointing to said UE, said S-CSCF or P-CSCF carry medium route indication information in the INVITE of transmitting to UE, and notifying this UE said is its media routing mode of selecting.

In addition, the UE that also preserves according to this locality of said P-CSCF or the S-CSCF information that is linked into home network is carried out said route pattern decision-making;

The information that said UE is linked into home network comprises that home network is its IP address allocated; The access information that said UE inserts the visit net comprises the IP address that UE is linked into the visit net;

Also comprise in the said medium route indication information: the employed media communication of this UE address.

In addition, said P-CSCF comprises the indication information that requirement subscription UE is linked into the access information of visit net in the authentication request that the PCRF of home network sends;

After subscribing to successfully, when the access information of this UE of correspondence visit net changed or nullifies, the PCRF of said home network was to P-CSCF this variation of notice that sends a notification message.

In addition, said P-CSCF comprises the indication information that requirement subscription UE is linked into the access information of home network in the authentication request that the PCRF of home network sends;

After subscribing to successfully, when the access information of this UE home network changed or nullifies, the PCRF of said home network was to P-CSCF this variation of notice that sends a notification message.

In sum; Adopt method of the present invention, be applied to the IMS access network, after UE roams into the visit net; Can effectively solve the IMS home network and can't know that whether UE produces the problem of pattern in this locality of support media route, and then can be that this UE selects the media routing mode optimized.

Description of drawings

Fig. 1 is network element entity and the annexation sketch map thereof relevant with the present invention in the IMS architecture in the prior art;

Fig. 2 is each main network element entity and annexation sketch map thereof under the PCC framework of 3GPP standard R7 version in the prior art;

Fig. 3 A is the roaming scence sketch map of available technology adopting mobile IP technology;

Fig. 3 B is the method sketch map of the solution medium alternate route that the 3GPP tissue proposes in the prior art;

Fig. 4 A～4C is in the prior art, and under the SAE framework, UE is positioned at visited network, produces the reference hierarchy configuration diagram that pattern is carried out the medium conversation through this locality;

Fig. 5 is in the prior art, after UE roams into the visit net, sets up the method flow diagram that IP carries at the visit net;

Fig. 6 is in the prior art, and after UE had set up the IP carrying, when being registered to the IMS system, P-CSCF and PCC carried out mutual method flow diagram;

Fig. 7 is in the prior art, UE under roaming condition, the method flow diagram that makes a call for its IP address allocated with home network;

Fig. 8 sets up the method flow diagram that visit net IP carries for embodiment of the invention UE;

Fig. 9 carries the method flow diagram to P-CSCF for the embodiment of the invention is linked into the access information of visiting net with UE when registering;

Figure 10 is that the embodiment of the invention is linked into the method flow diagram that the access information of visiting net sends to P-CSCF with UE when setting up visit net IP carrying;

Figure 11 carries out medium method of routing flow chart for embodiment of the invention home network;

Figure 12 carries the method flow diagram to P-CSCF for the embodiment of the invention with the access information that UE is linked into the visit net.

Embodiment

UE sets up visit net IP and carries in the visit net, and sets up the process that home network IP carried and be registered to the IMS home network, makes UE can use this locality of medium route to produce pattern or home network route pattern.Said process can be divided into following three kinds of situation:

(1) UE sets up the IP carrying in home network, and after successfully being registered to the IMS home network, roams into the visit net, and this moment, UE kept the IP carrying of home network, and has set up the IP carrying of visit net;

(2) UE nets start in visit, sets up the IP carrying of home network, the IP carrying of visit net, utilizes the IP carrying of the home network of having set up to be registered to the IMS home network then; UE sets up home network IP and carries and can set up before visit net IP carries, also can after;

(3) UE is in the start of visit net, and the IP that sets up home network earlier carries, and is registered to the IMS home network then, and the IP that sets up the visit net at last carries.

Set up in the process of the IP carrying of visiting net at UE, the V-PCRF of visit net is linked into the H-PCRF that the information of visiting net sends to home network with UE.If UE had carried out the IMS registration before, then H-PCRF uses the P-CSCF information of storage, and the access information that UE is linked into the visit net sends to P-CSCF; If UE initiates the IMS registration after setting up visit net IP carrying, then H-PCRF sends to P-CSCF with the access information that UE is linked into the visit net in this registration process.P-CSCF can pass through the home network internal process, and this information is carried to S-CSCF.So far; After the IMS home network can know that the UE that is positioned at visit net can adopt this locality to produce pattern to carry out the medium communication; Then can carry out the medium Route Selection; Adopt the local mode that produces pattern or home network route to carry out the medium communication, also can force UE to adopt a kind of in the dual mode to carry out the medium communication to specific transactions.

Fig. 8,9,10, the 11st, embodiments of the invention are used to be described under the roaming scence of the present invention, and how the IMS home network correctly knows the employable media routing mode of UE, further carries out the medium method of routing.

Fig. 8 sets up the method flow diagram that visit net IP carries for embodiment of the invention UE.This embodiment has described UE and has been positioned at the visit net, and when setting up visit net IP carrying, the access information that UE is linked into the visit net carries the process to H-PCRF.

Step 801, UE is positioned at the visit net, after the GW (PCEF) that links to each other with V-PCRF in the visit net receives the IP carrying foundation request of UE, for UE distributes an IP address;

Above-mentioned IP is carried the home network sign of carrying UE in the request of foundation.

Step 802; PCEF need check whether UE is authorized to insert; Also need be retrieved as information such as UE configured strategy and charging; Promptly need carry out PCC authorization check and acquisition strategy control and charge information, so PCEF sets up indication request, request user's strategy and charging relevant information to the V-PCRF of visit net transmission IP carrying;

Whether strategy and charging relevant information comprise: allow to insert, information such as the bandwidth of admissible service, permission, online and offline charging entrance.

Above-mentioned IP is carried and is set up the home network sign of carrying UE in the indication request.

Step 803, V-PCRF roams and detects and strategic decision-making; Do not belong to this visit net if detect this UE, then need carry out with the H-PCRF of home network alternately, carry out next step;

V-PCRF can set up the home network sign of carrying in the indication request according to the IP carrying and judge whether UE belongs to this visit net.

Step 804, V-PCRF sends request to the H-PCRF of home network, and subscriber policy and charging regulation information are returned in request;

In this was asked, V-PCRF had carried UE and has been linked into the access information that visit is netted, and netted IP address etc. like the knowledge of visit network mark, IAD identification information (title of PDN GW or address), visit that UE inserts.

Step 805, H-PCRF stores the access information that above-mentioned UE is linked into the visit net in this locality, be convenient in subsequent process, to P-CSCF this information is provided.

Step 806, if do not have user's subscriber policy and charging regulation information on the H-PCRF, PCRF is to SPR request user's strategy and charging regulation information;

Step 807, receive the above-mentioned request that H-PCRF sends after, SPR prepares corresponding data (subscriber policy and charging regulation information), and returns to H-PCRF;

Step 808, H-PCRF utilizes the information of obtaining from SPR, produces the strategic decision-making and the charging regulation of home network;

Step 809, H-PCRF returns the strategic decision-making and the charging regulation information of home network to V-PCRF;

Step 810 after V-PCRF receives the strategic decision-making and charging regulation information of H-PCRF transmission, produces the strategic decision-making and the charging regulation of visit net;

Step 811, strategic decision-making and charging regulation that V-PCRF will visit net send to GW (PCEF), and GW (PCEF) carries out this strategic decision-making;

Step 812, at least one PCC rule is successfully activated, and GW (PCEF) notice media bearer is successfully set up;

Do not have basic carrying to set up mandate if there is the PCC rule successfully to be activated, then show, can not set up carrying.

The access information that UE is linked into the visit net shown in Figure 8 carries the process to H-PCRF; The IP that is equally applicable to work as for UE served carries the situation that changes or nullify; Promptly change or when nullifying when carrying for the IP of the visit net that UE served, the access information of the visit net that can will upgrade through said method is notified the H-PCRF of home network.

In the described flow process of Fig. 8, storage UE is linked into the access information that visit is netted to H-PCRF in this locality, and this information can retrieve according to the sign of UE.IAD sign, UE that this information can comprise the visit net that the visit network mark is known, UE inserted of following main contents: UE access are linked into visit net assigned IP address.

If UE has set up the IP carrying of home network and the IP carrying of visit net before carrying out the IMS registration, then can be based on the sign of the UE in the IP beared information, with two IP bearing associations belonging to UE together.That is to say; When the UE execution is registered to the IMS home network; When P-CSCF requires PCRF will belong to the SIP session of UE with the home network IP carrying that belongs to UE to bind; PCRF can further be in the same place SIP session and the visit net IP bearing association that distributes for UE, further can be in the message response of PCRF to P-CSCF, and the access information that UE is linked into the visit net returns to P-CSCF.

Fig. 9 is according to the embodiment of the invention of this thought and the access information that UE is linked into the visit net is carried the method flow diagram to P-CSCF when the registration.This embodiment has described UE and has been positioned at the visit net, and UE carries out the IMS registration process after setting up visit net IP carrying; Through the IMS registration process, the access information that UE is linked into the visit net carries the process to P-CSCF.

S901～S903, UE are linked into the visit net, and according to the net loaded process of setting up of visit shown in Figure 8, the IP that has set up the visit net for UE carries; In loading establishing process, the UE that H-PCRF receives and storage V-PCRF sends is linked into the access information of visit net;

So far, UE has been assigned with the IP carrying of visit net in the visit net.

S904, UE are to the registration of IMS home network, and promptly UE sends the SIP register requirement to the P-CSCF of IMS home network;

Under the described scene of present embodiment, registration is initiated in the home network IP address (being H-IP) that UE uses home network to distribute.

After S905, P-CSCF receive the register requirement of UE, according to normal flow, with forwarding next node before the register requirement to;

S906, after having accomplished operation such as the authentication in the registration process, the IMS home network is sent 200OK message to P-CSCF, shows that the registration of UE is successful;

S907, P-CSCF gives UE with the 200OK forwards; After UE receives 200OK message, known successfully registration;

S908, after UE succeeded in registration, P-CSCF sent authentication request (DiameterAA-Request to H-PCRF; Be called for short AAR); Require PCRF that UE is carried out the inspection of medium authentication, require PCRF to carry out binding session simultaneously, promptly require the home network IP carrying of UE and the SIP session of UE are bound;

P-CSCF comprises the IP address information of UE and the sign of UE at least in AAR request, make PCRF to bind according to the IP carrying that the IP address of UE is distributed with the SIP session with for UE.

After S909, H-PCRF receive the AAR request that P-CSCF sends, will belong to the SIP session of UE and the IP that distributes for UE carries and binds, the PCC rule of correspondence is bound with it simultaneously;

In addition, in this step, H-PCRF removes and carries out the home network IP carrying of UE and the SIP binding session of UE, also need be according to UE home network IP loaded information, with the home network IP carrying of UE and net loaded the associating of visit of UE.Related essential information is: the sign of UE.Through this association, H-PCRF can be linked into the access information of visit net for P-CSCF provides UE.

S910, bind successfully after, H-PCRF sends authentication response (DiameterAA-Answer is called for short AAA) to P-CSCF, confirms that medium authentication and binding session process accomplish;

In this response message, H-PCRF is linked into the access information of visiting net with UE simultaneously and returns to P-CSCF.

S911; If previous H-PCRF does not subscribe to the Media Stream incident of IP bearing bed to PCEF, like medium foundation, medium change, media break etc., then PCRF sends re-authentication requests (Diameter Re-Auth-Request to GW (PCEF); Be called for short RAR) order, to subscribe to such incident.This request passes to GW (PCEF) via V-PCRF;

S912, GW (PCEF) confirm that H-PCRF subscribes to successfully the media event that belongs to this UE, send discrimination weight response (Diameter Re-Auth-Answer is called for short RAA) message to H-PCRF.Message arrives H-PCRF via V-PCRF.

In flow process shown in Figure 9, H-PCRF utilizes the registration process of UE, and the UE that is stored on the H-PCRF when UE is set up visit net IP carrying is linked into the access information of visit net, and S910 offers P-CSCF through step.P-CSCF preserves this information, and can further this information be passed to S-CSCF behind the access information that receives UE access visit net in this locality.

If the process that UE foundation visit net IP carries is after UE carries out the IMS registration through home network IP carrying, then H-PCRF can't pass to P-CSCF with the access information that UE be linked into the visit net through the IMS registration process of UE.But in UE execution IMS registration process, H-PCRF can be recorded as the address of the P-CSCF of this UE service, and when follow-up UE set up visit net IP carrying, H-PCRF sent to P-CSCF with the access information that UE is linked into the visit net.

Figure 10 sends to the method flow diagram of P-CSCF for the access information that when setting up visit net IP and carry, UE is linked into the visit net according to the embodiment of the invention of this thought; This embodiment has described UE and has used home network IP carrying to be registered to the IMS home network earlier, and the IP that sets up the visit net then carries; In the process of setting up visit net IP carrying, H-PCRF sends to P-CSCF with the access information that UE is linked into the visit net.

S1001, UE are to the registration of IMS home network, and promptly UE sends the SIP register requirement to the P-CSCF of IMS home network;

Under the described scene of present embodiment, the home network IP address that UE uses home network to distribute is that H-IP initiates registration.

After S1002, P-CSCF receive the register requirement of UE, according to normal flow, with forwarding next node before the register requirement to;

S1003, after having accomplished operation such as the authentication in the registration process, the IMS home network is sent 200OK message to P-CSCF, shows that the registration of UE is successful;

S1004, P-CSCF gives UE with the 200OK forwards; After UE receives 200OK message, known successfully registration;

S1005, after UE succeeded in registration, P-CSCF sent authentication request (DiameterAA-Request to H-PCRF; Be called for short AAR); Require PCRF that UE is carried out the inspection of medium authentication, require PCRF to carry out binding session simultaneously, promptly require the home network IP carrying of UE and the SIP session of UE are bound;

After S1006, H-PCRF receive the AAR request of P-CSCF, will belong to the SIP session of UE and the IP that distributes for UE carries and binds, the PCC rule of correspondence is bound with it simultaneously;

And, the contact details (address information and/or identification information) that H-PCRF extracts and preserves this P-CSCF, and this information and the home network IP carrying of UE are carried out related, maybe carry out related with UE this information.See that from the angle of H-PCRF this P-CSCF is the P-CSCF for this UE service appointment.

S1007, bind successfully after, H-PCRF sends authentication response (DiameterAA-Answer is called for short AAA) to P-CSCF, confirms that medium authentication and binding session process accomplish;

S1008; If previous H-PCRF does not subscribe to the Media Stream incident of IP bearing bed to PCEF; Like medium foundation, medium change, media break etc., then PCRF sends re-authentication requests (Diameter Re-Auth-Request is called for short RAR) order to PCEF; To subscribe to such incident, this order sends to GW (PCEF) via V-PCRF;

S1009, GW (PCEF) confirm that H-PCRF subscribes to successfully the media event that belongs to this UE, send discrimination weight response (Diameter Re-Auth-Answer is called for short RAA) message to H-PCRF; This response message arrives H-PCRF via V-PCRF.

So far, UE successfully is registered to the IMS home network.Afterwards, UE will set up the IP carrying of visit net.

S1010, the GW (PCEF) of visit net receive the request of the foundation visit net IP carrying of UE, and V-PCRF is given in request, and request strategy and charging regulation; Because UE is a roaming state, so V-PCRF is given to request the H-PCRF of home network;

Through above-mentioned a series of requests, the access information that UE is linked into the visit net is sent out to H-PCRF.

S1011, H-PCRF store the access information that the UE that carries in this request is linked into the visit net after receiving above-mentioned IP carrying foundation request;

S1012, H-PCRF obtain this user's strategy and charge information, formulate corresponding strategy and charging regulation, and it is returned to V-PCRF, and to GW (PCEF), PCEF carries out should rule with rule downloading for V-PCRF; If regular successful execution, then the IP of visit net carries and is successfully set up;

S1013～S1014; After the IP of visit net carries successfully foundation; H-PCRF carries out the visit net IP carrying of this UE and the home network IP carrying of this UE related; And find the P-CSCF that serves for this UE, and utilizing the address information of this P-CSCF, the access information that UE is linked into the visit net sends to P-CSCF;

S1015, P-CSCF receive and storage UE is linked into the access information that visit is netted;

S1016, P-CSCF send to H-PCRF and confirm response.

In flow process shown in Figure 10, H-PCRF utilizes the registration process of UE, is stored as the P-CSCF address information of UE service, and the access information that when UE sets up visit net IP and carries, UE is linked into the visit net is notified to this P-CSCF.

Through the method shown in the embodiment of Fig. 9 and Figure 10; H-PCRF can set up that visit net IP carries or UE when being registered to the IMS home network at UE; The access information that UE is linked into the visit net is successfully notified to the P-CSCF for this UE service; P-CSCF can further pass to S-CSCF with information, and S-CSCF can store this information in this locality.

After the process of accomplishing Fig. 9 or Figure 10; P-CSCF, S-CSCF can utilize the UE that is obtained to be linked into the access information of visit net; For the calling of UE initiation, or exhale the end of sensing UE, according to local policy or customer service configuration; Whether decision requires UE to adopt the media routing mode of appointment, and further notifies UE to adopt the media routing mode of appointment.

Figure 11 carries out medium method of routing flow chart for embodiment of the invention home network.This embodiment has described when UE makes a call or exhaled eventually; The S-CSCF of IMS home network (also can be P-CSCF); Be linked into the access information of visit net according to the UE that self stores; And the access information of the home network of being stored in the UE registration process, judge whether UE can use this locality of medium route to produce pattern, can judge whether the key element decision adopts specific media routing mode to carry out the medium communication according to local policy, customer service configuration etc. further.

Step 1101, S-CSCF receives and exhales the end of pointing to UE; Or S-CSCF receives the calling that UE initiates;

Exhale above-mentioned end message to carry media negotiation information in the message with rising to exhale;

Step 1102, S-CSCF is linked into the access information of visit net according to the UE that self stores, and UE is registered to institute's canned data in the process of home network, judges that the current this locality of medium route of whether can using of UE produces pattern;

Step 1103, S-CSCF determines the media routing mode that UE uses according to customer service configuration and/or local policy, said media routing mode is meant: use this locality to produce pattern, or use the home network route pattern;

Step 1104 if S-CSCF need specify the employed media routing mode of UE, is not this route pattern and current UE is used, then notifies UE to use the media routing mode of this appointment.

If the calling procedure that UE initiates, S-CSCF can give UE through sending 380 message, and this message is a message that requires UE to attempt other service (Altemative Service).In this message, carry the medium route indication information that requires UE to make a call with designated mode.

If call out is to exhale the end of pointing to UE, and S-CSCF can carry medium route indication information when INVITE (invitation) request is transmitted to UE, require UE to carry out the medium communication with specific media routing mode, also can specify the employed media communication of UE address.

S-CSCF has only when need specify the employed media routing mode of UE; Just need through 380 message (be directed against UE rise exhale); Or, notify UE to use specific media routing mode through specifying the medium routing iinformation (being exhaled eventually) in the media negotiation among the INVITE to UE.If S-CSCF does not need to specify, then handle according to existing procedure.

After step 1105, media routing mode consulted to accomplish, S-CSCF continued to handle the subsequent session process.

In flow process shown in Figure 11; That carry out the media routing mode decision-making is S-CSCF; Equally; P-CSCF also can judge which kind of media routing mode UE uses according to decision elements such as local policys, and the reciprocal process of the reciprocal process of P-CSCF and UE and above-mentioned S-CSCF shown in Figure 11 and UE is identical.

Through Fig. 9,10, the flow process shown in 11; Can reach the IMS home network and know that UE is linked into the access information of visit net; Judge that in view of the above this locality that UE can the support media route produces; Thereby can realize decision-making according to key elements such as local policy or customer service configurations to the medium Route Selection of UE.

Wherein, Fig. 9, Figure 10 have described IMS home network (is access point with P-CSCF) and how to have obtained the access information that UE is linked into the visit net.Under two kinds of patterns, H-PCRF need adopt the sort of mode according to the difference judgement of scene actually, for H-PCRF, need do extra judgment task.In order to reduce this judgement requirement; For how letting H-PCRF notice P-CSCF be linked into the access information of visit net about particular UE; Can adopt following method: at any time in (being that UE sets up the IP carrying or UE carries out the IMS registration process); If H-PCRF can be known as the P-CSCF that UE serves, then H-PCRF can notify the access information that UE be linked into visit net to P-CSCF.Further, H-PCRF can notify the access information of all Access Networks of this UE to P-CSCF, is made a decision by P-CSCF.

Figure 12 carries the method flow diagram to P-CSCF for improvement embodiment of the present invention with the access information that UE is linked into the visit net.In Figure 12, S1201～S1204 is that UE sets up the process that visit net IP carries, and S1205～S1211 is that UE uses home network IP to carry the process of carrying out the IMS registration.For the convenience of describing, on this figure, described UE earlier and set up the process that IP carries, and then described UE and use home network IP to carry the process of carrying out the IMS registration.But, abideing by spirit of the present invention, UE sets up the process that home network IP carries, can be after UE uses the process of home network IP carrying carrying out IMS registration.For this situation, the described method of Figure 12 is used in the same old way, therefore repeats no more.

S1201～S1204 is that UE is linked into the visit net, sets up the process that visit net IP carries according to flow process shown in Figure 8; Carry in the process of setting up at IP, the UE that H-PCRF receives and storage V-PCRF sends is linked into the access information of visit net;

In step S1204, if H-PCRF can be known as the P-CSCF that UE serves, then H-PCRF sends the access information that UE is linked into the visit net to P-CSCF;

S1205～S1211 is that UE uses home network IP to carry the process of carrying out the IMS registration.Succeed in registration at IMS, P-CSCF is after UE sends 200OK message, and P-CSCF sends AAR message to H-PCRF, requires to carry out the binding of SIP session and IP carrying, and carries authentication.

As further optimization of the present invention, in step S1209, P-CSCF can also further require to subscribe to the access information of UE visit net.As response, in step S1211, if exist UE to be linked into the access information of visit net on the H-PCRF, then H-PCRF offers P-CSCF through the AAA response.

In addition, in step S1209, P-CSCF can require to subscribe to the access information that UE is linked into all-network, no matter is home network or visit net; Therefore in step S1211, H-PCRF can return the access information that UE is linked into all-network, no matter is home network or visit net.

Through the subscription procedure of S1209, H-PCRF can after the UE information that is linked into network change or just this information sent to P-CSCF through notification message when nullifying.

The method of the invention can be applicable to that UE roams under the various access situation of visit net; Be not only applicable to UE and can use home network route pattern and this locality to produce pattern simultaneously, be applicable to yet and only support home network route pattern and this locality to produce a kind of application scenarios in the pattern.Be the method for the invention, can not only satisfy the scene shown in Fig. 4 A, be suitable for too for the scene shown in Fig. 4 B, the 4C.

Claims

1. the method for a home network under roaming status selection media routing mode is characterized in that this method comprises the steps:

Set up that visit net IP carries or visit net IP carries and changes or when nullifying at UE, the access information that the "Policy and Charging Rules Function PCRF of visit net inserts the visit net with this UE sends to the PCRF of home network, and the PCRF of home network preserves this information;

The PCRF of home network sends to above-mentioned access information the Proxy Call Session Control Function P-CSCF that the home network of service is provided for this UE;

Call for and ask or when pointing to the final call request of this UE, the P-CSCF of home network or service call conversation control function S-CSCF are this UE selection media routing mode according to above-mentioned access information receiving rising of this UE.

2. the method for claim 1 is characterized in that,

Set up that visit net IP carries or visit net IP carries and changes or when nullifying at UE, the access information that the PCRF of visit net inserts the visit net with said UE is included in the PCRF that sends to home network in strategy and the charging regulation message of request home network.

3. the method for claim 1 is characterized in that,

The access information that said UE inserts the visit net comprises sign and following one or more the combination of UE: the Access Network sign of said visit net, and the IAD sign of said visit net, UE is linked into the IP address of visit net.

4. the method for claim 1 is characterized in that,

Initiate registration at UE to home network, after the PCRF of home network receives the authentication request of said P-CSCF transmission, insert the access information that visit is netted, then it is included in the authentication response and sends to said P-CSCF if this locality stores said UE.

5. the method for claim 1 is characterized in that,

Initiate registration at UE to home network, after the PCRF of home network receives the authentication request of said P-CSCF transmission, preserve the incidence relation of said P-CSCF and UE;

6. like claim 4 or 5 described methods, it is characterized in that,

The sign that comprises said UE in the said authentication request; Said UE inserts the sign that comprises UE in the access information of visiting net;

7. method as claimed in claim 6 is characterized in that,

If local preserve the access information that this UE inserts the visit net, after the PCRF of said home network receives said authentication request, the sign of using UE with the home network IP of UE carry with the visit of UE net loaded carry out related.

8. method as claimed in claim 4 is characterized in that,

The PCRF of said home network also is included in said authentication response with the access information of home network and sends to said P-CSCF.

9. the method for claim 1 is characterized in that,

Call for and ask or when pointing to the final call request of this UE receiving rising of said UE; Said P-CSCF or S-CSCF carry out the route pattern decision-making based on the access information that said UE inserts the visit net, judge that the current this locality of medium route of whether can using of this UE produces pattern;

10. method as claimed in claim 9 is characterized in that,

Call for and ask or when pointing to the final call request of this UE receiving rising of said UE; If the current use of said UE is not that said S-CSCF or P-CSCF are its selected media routing mode, then S-CSCF or P-CSCF will notify to this UE for its selected media routing mode through send message to UE.

11. method as claimed in claim 10 is characterized in that,

Call for and ask receiving rising of said UE, said S-CSCF or P-CSCF through 380 message that medium route indication information is carried in transmission, notify that this UE is said to be its media routing mode of selecting in the process of carrying out media negotiation;

12. method as claimed in claim 11 is characterized in that,

The UE that said P-CSCF or S-CSCF also preserve according to this locality is linked into the information of home network and carries out said route pattern decision-making;

13. like claim 4 or 5 described methods, it is characterized in that,

Said P-CSCF comprises requirement and subscribes to the indication information that UE is linked into the access information of visit net in the authentication request that the PCRF of home network sends;

After subscribing to successfully, when the access information of this UE of correspondence visit net changed or nullifies, the PCRF of said home network sent a notification message to P-CSCF and notifies said variation or cancellation.

14. method as claimed in claim 13 is characterized in that,

Said P-CSCF comprises requirement and subscribes to the indication information that UE is linked into the access information of home network in the authentication request that the PCRF of home network sends;

After subscribing to successfully, when the access information of this UE home network changed or nullifies, the PCRF of said home network was to P-CSCF send a notification message notice this variation or cancellation.