CN100454914C

CN100454914C - Building method for calling route from circuit switching network to IMS network

Info

Publication number: CN100454914C
Application number: CNB2005100699500A
Authority: CN
Inventors: 朱东铭; 武亚娟
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2005-03-25
Filing date: 2005-04-30
Publication date: 2009-01-21
Anticipated expiration: 2025-04-30
Also published as: CN1838649A

Abstract

The present invention discloses a building method for a calling route from a circuit switching network to an IMS network. An MGCF has the function of converting an E. 164 number to SIP-URI in an IMS network. The method also comprises the following steps: A. after the MGCF having the function of converting an E. 164 number to SIP-URI receives calling carrying an E. 164 number for indicating called UE from calling UE in a circuit switching network, the E. 164 number carried by the calling is converted to SIP-URI by the function of converting E. 164 number to SIP-URI, and an SIP message carrying the converted SIP-URI is built and is sent to I-CSCF; B. the I-CSCF queries the routing message preserved by HSS and obtains the routing information of the called UE which is UE indicated by the SIP-URI carried by the SIP message; according to the routing information of the called UE, the SIP message is sent to the called UE, then the called UE and the calling UE are in the SIP dialogue negotiation process, and the calling is completed.

Description

A kind of circuit exchange network to IMS network is called out the method for building up of route

Technical field

The present invention relates to set up the technology of calling out route in internet protocol multimedia subsystem (IMS) network, particularly a kind of circuit exchange network to IMS network is called out the method for building up of route.

Background technology

Along with the development of broadband network, mobile communication not only is confined to traditional voice communication, and can be in conjunction with multiple media business such as audio frequency, video, picture and texts.Multiple media business by with present that business (presence), short message, webpage (WEB) are browsed, the combining of data service such as locating information, propelling movement business (PUSH) and file-sharing, can satisfy the multiple demand of subscriber equipment (UE).

Under the promotion of several data service application, normal structure such as 3GPP and 3GPP2 has all successively been released the IMS framework, purpose is to use a kind of standardization open architecture to realize diversified multimedia service application in the mobile network, offers more selection of UE and abundanter impression.

At 3GPP version 5 (R5, Release) stage, introduced IMS, IMS is superimposed upon on the packet field network, is made up of CCF (CSCF), MGCF (MGCF), media resource function (MRF) and home signature user server functional entitys such as (HSS).Wherein CSCF can be divided into serving CSCF (S-CSCF), proxy CSCF (P-CSCF) and three logic entities of inquiry CSCF (I-CSCF) again.S-CSCF is the service switching center of IMS, carries out session control, and peace preservation association's speech phase is in charge of UE information, produces charge information etc.; P-CSCF is the access point that UE inserts IMS, finishes the UE registration, is responsible for service quality (QoS) control and safety management etc.; I-CSCF is responsible for the intercommunication between the IMS territory, and network topology and configuration are externally hidden in distribution and the selection of management S-CSCF, produce metering data etc.The MGCF control gateway realizes the intercommunication of IMS and other network.MRF provides media resource.The subscription data of HSS storage UE and configuration information etc.

In IMS, use the signaling control protocol of Session Initiation Protocol as IP multimedia session; Use Diameter to carry out information interaction on the Cx interface between HSS and I-CSCF and HSS and the S-CSCF.

IMS is applied in packet network, wireless local (WLAN) network or the next generation (NGN) network that defines among the 3GPP2.

When UE will insert IMS, must use public user identity to register to the IMS network side, public user identity is used for identifying UE at the IMS network, public user identity can use the unified resource identifier (SIP-URI, Session Initiation Protocol UniformResource Indentifier) that is used for Session initiation Protocol.A UE can have one or more public user identity.

The call set up signaling flow chart from circuit exchange network to IMS network of Fig. 1 for stipulating in the IMS network standard supposes that circuit-switched network is public phone exchanges network (PSTN), and its concrete steps are:

Step 100, PSTN send initial address message (IAM) message to MGCF, and this message is carried relaying sign and the purpose information that can call out called UE.

After step 101, MGCF receive this message, on loading end, set up from PSTN through the connection of MGW to packet switching network by H.248 ordering.

Step 102, MGCF structure Session initiation Protocol visit (SIP INVITE) request, comprising media description information, the follow-up routing procedure (S-S routing procedure) that enters S-CSCF to S-CSCF.

Step 103, by S-S routing procedure MGCF receive carry called UE Media Stream ability reply (Offer Response) message, promptly on signaling plane, obtain the Media Stream ability of called UE.

Step 104, MGCF and guide MGW to reserve the session resource requirement by H.248 ordering modification to connect parameter.

The required media resource of session that step 105, MGCF decision can provide is confirmed the Offer Response message of step 103, returns the message (Response Conf) of local reservation situation, and promptly the Offer Response affirmation message of replying is given the opposite end.

Step 106, opposite end echo reply message (Conf Ack), i.e. the affirmation message of Response Conf message.

Media gateway in step 107, the circuit-switched network (MGW) reserved resource.

After step 108, resource reservation were finished, MGCF returned success the message (Reservation Conf) of reserved resource and gives the opposite end.

Step 109, opposite end echo reply message (Reservation Conf) are given MGCF.

Ring (Ringing) process is carried out in step 110, opposite end.

Step 111, MGCF finish message (ACM, AddressComplete Message) for PSTN forwarded address.

After reply step 112, opposite end, MGCF will receive the final response of SIP 200OK message conduct that called UE sends.

Step 113, MGCF transmit response message (ANM, Answer Message) and give PSTN.

Step 114, MGCF can begin the transmission of Media Stream by H.248 ordering notice MGW.

Step 115, MGCF return the affirmation message SIP ACK to SIP 200OK.

Here said S-S routing procedure refers to such an extent that be the process that how S-CSCF is routed to sip message called UE in the IMS network, and as shown in Figure 2, Fig. 2 is call ending S-S routing procedure signaling diagram when PSTN.Wherein, Breakout Gateway Control Function (BGCF, Breakout Gateway ControlFunction) is the interface between S-CSCF and the PSTN network, and the detailed description process can be with reference to TS23.228 chapters and sections 5.5.3.Each step among Fig. 2 all can be connected with the described step of Fig. 1, according to present IMS specification description, in the IMS network MGCF is considered as a S-SCSF, therefore, if the calling UE of initiation session is the UE that is arranged in the PSTN network, it is exactly the MGCF that receives the PSTN calling network that the S-CSCF that then is arranged in the ownership IMS network at called UE place among Fig. 2 is considered to.

In existing IMS standard, many places describe and process description in all MGCF to be considered as be the MGCF of and S-CSCF par, difference only is that MGCF does not trigger professional control, and wants the conversion between support circuit-switched network signal and the SIP signaling.But according to residing status of MGCF and realization function, MGCF should be more as a P-CSCF rather than S-CSCF, and this is because there is the function MGCF of a lot of S-CSCF all can't realize, for example, S-CSCF will preserve IMS user's CAMEL-Subscription-Information, does not then preserve on the MGCF; S-CSCF will preserve the routing iinformation that is addressed to called UE, does not then preserve on the MGCF.Therefore, consider that the status of MGCF and S-CSCF is different from the angle of signalling route.

Because MGCF stores IMS user's CAMEL-Subscription-Information and routing iinformation unlike S-CSCF, so the relaying sign that can't be directly carry according to the described IAM message of Fig. 1 and purpose information are routed to BGCF or P-CSCF the IMS network from PSTN, thereby further be routed to called UE, set up and call out.

In order to set up calling, MGCF must be routed to I-CSCF earlier, store the HSS of the IMS network user's CAMEL-Subscription-Information in advance by the I-CSCF inquiry, relaying identifies and the routing iinformation of the called UE of purpose information thereby obtain having, be routed to called UE again, but, can't be routed to I-CSCF, so can't adopt this mode to realize because MGCF can not trigger professional control.

Further, owing to the call signaling that sends from circuit-switched network, can only be the E.164 number that is used to represent relaying sign and purpose information as what IAM carried in circuit-switched network identification, rather than the SIP-URI that is used for recognition purpose information that can in the IMS network, discern, therefore, even MGCF can be routed to I-CSCF, also can't be according to the routing iinformation of number inquiry E.164 to called UE, thus make call establishment failure from circuit exchange network to IMS network.

As can be seen from the above analysis, there are mistaken ideas in location MGCF at present, is realizing that in the route, there is following several problem in the calling from circuit-switched network in the IMS network, thereby cause present routing procedure to realize, and follow-up business is handled also existence influence.

1, because MGCF does not store the IMS network user's CAMEL-Subscription-Information, can't determine and to be routed to BGCF or P-CSCF from the calling in the circuit-switched network, further be routed to called UE as S-CSCF.

2, because MGCF can't be routed to the CAMEL-Subscription-Information that I-CSCF goes to inquire about called UE, further can't be according to being used to represent the routing iinformation of the E.164 number inquiry of relaying sign and purpose information to called UE, thereby can't learn which current S-CSCF for the called UE service is, therefore can't be addressed directly to the S-CSCF that service is provided for called UE, thereby make S-CSCF can't carry out subsequent process.

3, suppose that MGCF can go to handle be routed to BGCF or P-CSCF from the calling in the circuit-switched network, thereby further be routed to called UE, but, can economize called UE slightly like this provides the professional control procedure of the S-CSCF of service, and S-CSCF is as the service node in the IMS network, can not be omitted, otherwise can cause the problem of aspects such as charging, safety.

In sum, can't realize the foundation of circuit exchange network to IMS network calling route at present.

Summary of the invention

In view of this, main purpose of the present invention is to provide a kind of circuit exchange network to IMS network to call out the method for building up of route, and this method can realize the foundation of circuit exchange network to IMS network calling route.

According to above-mentioned purpose, technical scheme of the present invention is achieved in that

A kind of circuit-switched network is to the method for building up of internet protocol multimedia subsystem IMS calling network route, number translated is the function of the unified resource identifier SIP-URI of Session initiation Protocol to be provided with E.164 for MGCF MGCF in the IMS network, and this method also comprises:

A, have number translated E.164 be the MGCF of the function of SIP-URI receive be used to indicate the calling of E.164 number of called UE from carrying of calling subscriber equipment UE in the circuit-switched network after, by number translated E.164 is that the E.164 number translated that the function of SIP-URI is carried this calling is SIP-URI, and structure carries the Session initiation Protocol sip message of the SIP-URI that is changed and sends to query call controlled function I-CSCF;

The routing iinformation of the UE that B, I-CSCF inquiry home signature user server HSS is preserved, obtain the routing iinformation of called UE, called UE is the UE of the entrained SIP-URI indication of sip message, routing iinformation according to called UE sends to called UE with sip message, called UE and calling UE are carried out SIP session negotiation process, finish this calling.

The process of steps A structure sip message is: SIP-URI is filled in the Request-URI field in the sip message of structure.

The described process that sip message is sent to called UE of step B is:

I-CSCF is defined as the serving-call session control function S-CSCF that called UE provides service according to the routing iinformation of the UE of the entrained SIP-URI inquiry HSS preservation of sip message, learns the route of this S-CSCF, and the sip message of being constructed is sent to this S-CSCF;

This S-CSCF is according to receiving that SIP-URI that sip message carries is established to the route of called UE, sends to called UE with sip message.

After the E.164 number translated that this calling is carried of steps A was SIP-URI, this method also comprised:

Described MGCF judges whether that the number translated E.164 passed through of success is that the E.164 number translated that the function of SIP-URI is carried this calling is SIP-URI, if carry out subsequent step; Otherwise, carry the replying of error message with returning to circuit-switched network, process or will call out calling UE in the error messages transtation mission circuit switching network by circuit-switched network.

When there is more than one HSS in the IMS network, and more than one HSS is during by signatory location-server SLF administration, and before the HSS of described inquiry storage called UE CAMEL-Subscription-Information, this method further comprises:

The SIP-URI inquiry SLF that I-CSCF carries according to sip message after determining to store the HSS of the called UE information with SIP-URI, carries out the step of the HSS of inquiry storage called UE routing iinformation again.

The process that the described sip message of steps A sends to I-CSCF is:

At MGCF the I-CSCF address is set in advance, MGCF sends to sip message to I-CSCF that should the address according to the I-CSCF address that is provided with;

Perhaps at MGCF an I-CSCF tabulation is set in advance, MGCF selects an I-CSCF according to set rule from the I-CSCF tabulation, sip message is sent to selected I-CSCF.

The function that described E.164 number translated is SIP-URI is an ENUM DNS interpretative function;

Perhaps be: the E.164 corresponding relation of number and SIP-URI is set, according to corresponding relation E.164 number translated be the function of SIP-URI.

Described MGCF is the MGCF of called UE ownership IMS network.

When described MGCF did not belong to the MGCF of IMS network for called UE, the described MGCF of steps A with the process that sip message sends to I-CSCF was:

Topology hiding Interworking gateway I-CSCF (THIG) in MGCF and the called UE ownership IMS network carries out Signalling exchange, obtains carrying out the I-CSCF of query function, sip message is sent to the I-CSCF of resulting execution query function again.

The I-CSCF of described I-CSCF (THIG) and execution query function is same I-CSCF.

From such scheme as can be seen, E.164 the present invention MGCF in the IMS network in advance is provided with that number translated is the function of SIP-URI, after the IMS network receives calling from circuit-switched network, the E.164 number translated that adopts MGCF is that the E.164 number translated that the function of SIP-URI is carried calling is the SIP-URI that can carry out route at the IMS network, utilize the SIP-URI structure sip message after changing, according to the routing iinformation of the SIP-URI after the conversion to I-CSCF inquiry called UE, I-CSCF passes through the route that inquiry HSS determines to arrive by the S-CSCF for the called UE service called UE, and sip message is sent to called UE by S-CSCF.The called UE and the calling UE that receive sip message are carried out SIP session negotiation process, finish this calling.Method provided by the invention has realized the foundation of circuit exchange network to IMS network calling route.

Description of drawings

The call set up signaling flow chart from circuit exchange network to IMS network of Fig. 1 for stipulating in the IMS network standard;

Fig. 2 is routed to sip message for the S-CSCF in the IMS network signaling process figure of called UE place ownership IMS network;

Fig. 3 sets up from the signaling process figure of the calling route of circuit exchange network to IMS network by I-CSCF for the present invention;

Fig. 4 sets up from the method flow diagram of the calling route of circuit exchange network to IMS network for the present invention.

Embodiment

In order to make the purpose, technical solutions and advantages of the present invention clearer, below lift specific embodiment and, the present invention is further elaborated with reference to accompanying drawing.

In order to realize the present invention, at first MGCF must be routed to I-CSCF with the calling from circuit-switched network, make I-CSCF inquiry HSS obtain the CAMEL-Subscription-Information and the routing iinformation of called UE, I-CSCF will be routed to the S-CSCF that provides service for called according to routing iinformation from the calling of circuit-switched network, further be routed to called UE.Wherein, from can be to the calling routing procedure of called UE place network, please refer to the description of corresponding chapters and sections the TS 23.228 to the calling routing procedure of called UE from called UE place network with reference to figure 2 described processes for the S-CSCF of called UE service.

The present invention can set in advance the address of I-CSCF at MGCF, has by the time from circuit-switched network at first will to be routed to by the sip message of Call Transfer after the calling that comes to have the I-CSCF that sets in advance the I-CSCF address.The present invention can not set in advance the I-CSCF address yet in MGCF, but an I-CSCF tabulation is set, after MGCF waits until calling next from circuit-switched network, from the I-CSCF tabulation, select an I-CSCF according to set rule, will send to selected I-CSCF by the sip message of Call Transfer.

Fig. 3 sets up from the signaling process figure of the calling route of circuit exchange network to IMS network by I-CSCF for the present invention, and its detailed process is:

Step 300, make a call in the calling UE of circuit-switched network, PSTN sends to MGCF in the IMS network with IAM message.

Step 301, MGCF by H.248 order set up on the loading end with PSTN between be connected.

Step 302, MGCF structure SIP INVITE, the message that structure is good sends to I-CSCF.

This I-CSCF can set in advance the I-CSCF of I-CSCF address for having MGCF, also can be the optional I-CSCF of MGCF.

Step 303, I-CSCF send position enquiring request (Location Query) to the HSS of storage called UE CAMEL-Subscription-Information, obtain the routing iinformation of called UE.

Step 304, HSS return the routing iinformation of called UE to I-CSCF.

Step 305, I-CSCF are determined to the S-CSCF that serves into called UE according to the routing iinformation of called UE, further are determined to the route of called UE, send the SIP INVITE for the S-CSCF for the called UE service.

Step 306～step 307, the S-CSCF that serves for called UE serve control and are transmitted to called UE according to the route of called UE the SIP INVITE being jumped functional entity by next called UE.

According to prior art, the termination network of the functional entity of next jumping of S-CSCF and this calling is relevant, and when this call ending during at the IMS network, this functional entity is P-CSCF; When this call ending during at the PSTN network, this functional entity is BGCF.

Step 308～310, called UE send Offer Response message to S-CSCF, and S-CSCF gives MGCF by I-CSCF with Offer Response forwards, the Media Stream ability of this message indication called UE.

Step 311, MGCF and guide MGW to reserve the session resource requirement by H.248 ordering modification to connect parameter.

The required media resource of session that step 312～314, MGCF decision can provide, MGCF is according to route that is determined to S-CSCF and the route that further arrives called UE, through I-CSCF with provide the S-CSCF of service that Response Conf is jumped functional entity by next to be transmitted to called UE for called UE.

Step 315～317, called UE are through returning ConfAck for called UE provides the S-CSCF of service and I-CSCF to MGCF.

Step 318, MGW reserved resource.

After step 319～321, resource reservation were finished, MGCF was through I-CSCF and provide the S-CSCF of service that Reservation Conf is transmitted to called UE by next jumping functional entity for called UE.

Step 322～324, called UE S-CSCF and the I-CSCF echo reply message (Reservation Conf) through service is provided for called UE is given MGCF.

Step 325～327, called UE are through carrying out the Ringing process for called UE provides the S-CSCF of service and I-CSCF.

Step 328, MGCF give PSTN forwarded ACM message.

After step 329～331, called UE were replied, S-CSCF through service is provided for called UE and I-CSCF sent SIP 200OK message to MGCF.

Step 332, MGCF send ANM to PSTN.

Step 333, MGCF can begin the transmission of Media Stream by H.248 ordering notice MGW.

Affirmation message SIP ACK to SIP 200OK is returned through I-CSCF with for called UE provides the S-CSCF of service in step 334～336, MGCF.

In the prior art, what carry from the calling of circuit-switched network is the E.164 number that is used to identify called UE information and relaying sign, because the IMS network is not supported E.164 number, so E.164 number translated is the SIP-URI of IMS network support, could finally inquire the routing iinformation of called UE with SIP-URI at HSS.So the E.164 number translated that for the purpose of the present invention, how to be routed to the routing iinformation of I-CSCF inquiry called UE and how will to carry from the calling of circuit-switched network is that the SIP-URI of IMS network support is indispensable.Below be that the process of the SIP-URI of IMS network support is specifically described to the E.164 number translated how will carry from the calling of circuit-switched network.

E.164 the present invention increases by MGCF in the IMS network, and number translated is the function of SIP-URI, as ENUM DNS interpretative function, when solving in the prior art from the called UE in the calling UE call IMS network of circuit-switched network, sip message can't carry out route in the IMS network, thereby can't be routed to S-CSCF under the called UE and the problem that further is routed to called UE.The database of the ENUM DNS interpretative function that sets in advance here, is to be provided with by the configuring condition of IMS Virtual network operator according to UE in the IMS network.One of ENUM DNS interpretative function is exactly to be the corresponding a series of URI of number E.164, thereby makes the E.164 telephone number of international uniform become the network address resources that can use in the IMS network.In the prior art, this ENUM DNS interpretative function is arranged among the S-CSCF.

The E.164 number translated that the present invention increases in MGCF is that the function of SIP-URI also can not be an ENUM DNS interpretative function, but E.164 number that is provided with and the corresponding relation of SIP-URI, inciting somebody to action E.164 according to corresponding relation MGCF, number translated is SIP-URI.

Increasing E.164 on the MGCF in the IMS network, number translated is the function of SIP-URI, making that the E.164 number that identifies called UE from the calling of circuit-switched network being used for of carrying can be converted into one can be at the SIP-URI of IMS network route, MGCF in the IMS network uses this SIP-URI through being converted to when the structure sip message, the I-SCSF that sends in the IMS network further handles, for the I-CSCF in the IMS network, just the same with processing SIP session of the prior art.

Below being used in MGCF increase ENUM DNS interpretative function is example, illustrates how the present invention sets up the calling route from circuit exchange network to IMS network.

Fig. 4 sets up from method embodiment one flow chart of the calling route of circuit exchange network to IMS network for the present invention, and this embodiment has increased ENUM DNS interpretative function at MGCF, and its concrete steps are:

Step 400, initiate to carry the E.164 calling of number in the calling UE of circuit-switched network, this calling is used for the called UE of call IMS network, and the E.164 number that this calling is carried is used to indicate the user ID of called UE.

The calling that step 401, calling UE are initiated sends to the MGCF in the IMS network under the called UE by circuit-switched network, and this MGCF is the Interworking gateway between the IMS network under circuit-switched network and the called UE.

After MGCF under step 402, the called UE in the IMS network receives this calling, E.164 the number translated of this calling being carried by the ENUM DNS interpretative function that is provided with is SIP-URI, according to prior art structure SIP INVITE, this message carries the SIP-URI through conversion.

SIP-URI through conversion is the public user identity that called UE is used in the IMS network.

The method of structure SIP INVITE is: will insert in the Request-URI field of SIPINVITE message through the SIP-URI of conversion, construct other fields of SIP INVITE then.These field makes are clearly definition in existing IMS standard TS 23.228, comprise: the head of Supposed field is changed to " 100rel ", insert a P-Asserted-Identity head, produce a unique IMS network billing sign and insert the head of P-Charging-Vector field, insert the parameter of sign MGCF place IMS network etc. at the head of P-Charging-Vector header field.

MGCF under step 403, the called UE in the IMS network will construct the I-CSCF that good SIP INVITE sends to the affiliated IMS network of called UE.

Behind the SIP-URI that step 404, the I-CSCF that receives the SIP INVITE carry according to this message, by Cx interface information query HSS, obtain providing the S-CSCF of service, be determined to the resulting route that the S-CSCF of service is provided for called UE for called UE with this SIP-URI.

I-CSCF receives that the processing procedure after the SIP INVITE is identical with prior art.

Step 405, the I-CSCF that receives the SIP INVITE send to the resulting S-CSCF that service is provided for called UE by the route of determining with this message.

Step 406, for after called UE provides the S-CSCF of service to receive this message, be determined to the route of called UE, this message is sent to called UE.

S-CSCF receives that the processing procedure after the SIP INVITE is identical with prior art.

Step 407, calling UE and called UE are carried out SIP session negotiation process, finish this calling.

The present invention constructs the SIP INVITE and is one and illustrates, MGCF can also construct other sip messages, the common trait E.164 number translated that to be exactly MGCF carry this calling by the ENUM DNS interpretative function that is provided with is SIP-URI, and structure carries the sip message of conversion back SIP-URI.

In the present invention, MGCF also can be the MGCF in any one IMS network, and the ownership IMS network at called UE place not necessarily.This is because because the strategy of IMS Virtual network operator is considered or the difference of IMS network design, in some cases, the calling that circuit-switched network is initiated may at first be sent to a MGCF in the IMS network, but this IMS network is the ownership IMS network of called UE not necessarily, therefore needs the further route of this MGCF.In this case, the MGCF that is not called UE ownership IMS network may need elder generation and called UE to belong to the I-CSCF of an execution topology hiding function in the IMS network, be topology hiding Interworking gateway (I-CSCF (THIG), I-CSCF (Topology Hiding Inter-working Gateway)) contact, obtain carrying out the I-CSCF of query function, I-CSCF with resulting execution query function gets in touch then, the CAMEL-Subscription-Information and the routing iinformation of inquiry called UE.The I-CSCF and the I-CSCF (THIG) that carry out query function can be same I-CSCF, also can be two I-CSCF independently.

Increase ENUM DNS interpretative function at MGCF, can't be converted to SIP-URI if call out the E.164 number that carries by ENUM DNS interpretative function, it is ENUM DNS inquiry failure, then can setting in advance according to the IMS network, this replying of error message of carrying from the calling of circuit-switched network is turned back to circuit-switched network, do further processing again by this circuit-switched network, perhaps, return the message that this calling makes mistakes for the calling UE of circuit-switched network according to error handling processing.

When having a plurality of HSS in the IMS network, I-CSCF needs to inquire about earlier the signatory location-server (SLF in the IMS network, Subscription Locator Function), can finish according to the SIP-URI structure Dx message of called UE at query script, the result that inquiry obtains is for preserving the HSS of the pairing called UE relevant information of this SIP-URI, and I-CSCF is current to this HSS transmission Cx information query more then is the S-CSCF of this SIP-URI institute corresponding UE service.

Circuit-switched network of the present invention can be public telephone network (PSTN).

Method provided by the invention and prior art are relatively independent, that is to say, existing S-CSCF supports what ENUM DNS interpretative function still existed.

MGCF among the present invention not only can be the MGCF in the IMS network under the called UE, also can be the MGCF in any IMS network.

By method provided by the invention, solved shortcoming of the prior art: because the present invention makes calling from circuit-switched network be routed to the routing iinformation of I-CSCF inquiry called UE and can be the SIP-URI of IMS network support with the E.164 number translated of carrying from the calling of circuit-switched network, so can will be routed to called UE by the S-CSCF of service is provided for called UE from the calling in the circuit-switched network, thereby can make called UE is carried out business control, finish charging and safety management called UE to called UE provides the S-CSCF of service.

By method provided by the invention, can solve the problem that can't in the IMS network, be routed to called UE when the calling UE of the existing circuit-switched network that exists and the called UE in the IMS network are set up the SIP session, the perfect enforcement and the application of IMS network, make the IMS network ripe more, more can adapt to the various network conditions in the specific implementation, improve user's satisfaction of using UE.

The above only is preferred embodiment of the present invention, not in order to restriction the present invention, all any modifications of being made within the spirit and principles in the present invention, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.

Claims

1, a kind of circuit-switched network is to the method for building up of internet protocol multimedia subsystem IMS calling network route, it is characterized in that, number translated is the function of the unified resource identifier SIP-URI of Session initiation Protocol to be provided with E.164 for MGCF MGCF in the IMS network, and this method also comprises:

2, the method for claim 1 is characterized in that, the process of steps A structure sip message is: SIP-URI is filled in the Request-URI field in the sip message of structure.

3, the method for claim 1 is characterized in that, the described process that sip message is sent to called UE of step B is:

4, the method for claim 1 is characterized in that, after the E.164 number translated that this calling is carried of steps A was SIP-URI, this method also comprised:

5, the method for claim 1, it is characterized in that when there is more than one HSS in the IMS network, and more than one HSS is during by signatory location-server SLF administration, before the HSS of described inquiry storage called UE CAMEL-Subscription-Information, this method further comprises:

6, the method for claim 1 is characterized in that, the process that the described sip message of steps A sends to I-CSCF is:

7, the method for claim 1 is characterized in that, the function that described E.164 number translated is SIP-URI is an ENUM DNS interpretative function;

8, the method for claim 1 is characterized in that, described MGCF is the MGCF of called UE ownership IMS network.

9, the method for claim 1 is characterized in that, when described MGCF did not belong to the MGCF of IMS network for called UE, the described MGCF of steps A with the process that sip message sends to I-CSCF was:

10, method as claimed in claim 9 is characterized in that, the I-CSCF of described I-CSCF (THIG) and execution query function is same I-CSCF.