WO2008151556A1

WO2008151556A1 - Method and system for assigning serving-call session control function

Info

Publication number: WO2008151556A1
Application number: PCT/CN2008/071225
Authority: WO
Inventors: Hui Li
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-06-14
Filing date: 2008-06-06
Publication date: 2008-12-18
Also published as: CN101325731A; CN101325731B

Abstract

A method and system for assigning Serving-Call Session Control Function and an application server are provided. The method comprises: a Home Subscriber Server receiving a request message sent by an Interrogating Call Session Control Function for storing a server address, the message including an address of the Serving-Call Session Control Function selected by the Interrogating Call Session Control Function for a user; the Home Subscriber Server detecting whether the address of the Serving-Call Session Control Function has been stored for the user locally, if it has been stored, the Home Subscriber Server returning the stored address of the Serving-Call Session Control Function back to the Interrogating Call Session Control Function; if it has not been stored, the Home Subscriber Server storing the address of the selected Serving-Call Session Control Function for the user and returning the address of the selected Serving-Call Session Control Function back to the Interrogating Call Session Control Function.

Description

Method and system for assigning service call session control function

Technical field

The present invention relates to the field of communications, and in particular, to a method and system for allocating a service call session control function. Background technique

IMS (IP Multimedia Subsystem, IP Multimedia Subsystem) is a subsystem superimposed on the existing packet domain in the WCDMA network added by the 3rd Generation Partnership Project (3rd Generation Partnership Project). The packet domain is the bearer channel for the upper layer control signaling and the media transmission, and the SIP (Session Initiation Protocol) protocol is introduced as the service control protocol. The SIP is simple, easy to expand, and the media combination is convenient. The bearer control is separated to provide rich multimedia services.

As shown in FIG. 1, it is a schematic diagram of a communication system architecture including an IMS network, and the communication system includes: an IMS, an application server (AS), a mobile network, an IP multimedia network, and a public switched telephone network. The IMS further includes a Call Session Control Function (CSCF), a Proxy-Call Session Control Function (P-CSCF), a Media Gateway (MG), and a Media Gateway Control Function ( Media Gateway Control Function (MGCF), Breakout Gateway Control Function (BGCF), Multimedia Resource Function Processor (MRFP), Multimedia Resource Function Controller (MRFC), user User Equipment (UE), Subscription Locator Function (SLF), Home Subscriber Server (HSS), etc.

In the prior art, the process of the IMS controlling the user registration request may be as shown in FIG. 2, including: Step 101: A User Equipment (User Equipment) located in the visited network initiates a registration request to the P-CSCF of the visited network;

Step 102, the P-CSCF obtains an I-CSCF (Interrogating-Call Session Control Function) address of the user home network according to the home network domain name of the user, and forwards the registration request to the I-CSCF; Step 103: The I-CSCF receives the registration request, and queries the HSS of the home network to query the user registration status by using the UAR message.

Step 104: If the user has already registered, the HSS will store the assigned S-CSCF address, and the HSS returns the S-CSCF (Serving-Call Session Control Function) address assigned by the user, I-CSCF. The route registration request is sent to the assigned S-CSCF, and the registration and allocation of the S-CSCF process ends. If the HSS check user is not registered, return the capability set of the home network S-CSCF to the I-CSCF through the UAA message, and perform step 105;

Step 105: The I-CSCF selects an appropriate S-CSCF according to the capability set of the S-CSCF, and forwards the user registration request information to the selected S-CSCF.

Step 106: The selected S-CSCF receives the registration request, and finds that the initial registration is performed, and the authentication set of the registered user is obtained from the HSS by using a UAR message.

Step 107: The HSS saves the address of the selected S-CSCF, and returns user authentication data to the selected S-CSCF by using a UAA message.

Step 108: The selected S-CSCF selects an authentication vector, and sends a 401 message to the I-CSCF for authentication, where the 401 message carries the selected authentication vector.

Step 109: The I-CSCF forwards a 401 message to the P-CSCF.

Step 110: The P-CSCF forwards a 401 message to the UE.

Step 111: The UE calculates an authentication response according to an authentication vector in the 401 message, and re-initiates a registration request to the P-CSCF.

Step 112: The P-CSCF forwards a registration request to the I-CSCF.

Step 113: The I-CSCF receives the registration request, and queries the HSS to query the user registration status by using the UAR.

Step 114: The HSS checks the user registration status, and finds that the S-CSCF address allocated for the user has been saved locally, and then returns the selected S-CSCF address to the I-CSCF through the UAA; Step 115, the I - the CSCF forwards the registration request to the selected S-CSCF according to the selected S-CSCF address;

Step 116: The selected S-CSCF detects an authentication response. If the authentication succeeds, the SAR message is used to request the HSS to download the subscription data of the user.

Step 117: The HSS updates the user registration information, and returns the user's subscription through the SAA message. Data to the selected S-CSCF;

Step 118, the selected S-CSCF returns a registration success confirmation message to the I-CSCF; Step 119, the I-CSCF returns a registration success confirmation message to the P-CSCF;

Step 120: The P-CSCF returns a registration success confirmation message to the UE.

In the process of implementing the present invention, the inventors have found that in the registration process of the above prior art, there may be the following problems:

When multiple terminals register with the same user, the first terminal registration message selects the first S-CSCF at the I-CSCF, and the HSS saves the first S-CSCF address. If the user registration is processed, before the HSS processes the MAR request of the first S-CSCF, the I-CSCF processes the registration message of the second terminal, and the I-CSCF registers the second S-CSCF for the second terminal registration, such that the second When the S-CSCF processes the second terminal registration message, it saves the second S-CSCF address in the HSS and overwrites the first S-CSCF address, which causes: The first terminal is registered in the first S-CSCF. The subsequent registration authentication request of the terminal cannot be received, and the user data is released by the network cancellation initiated by the HSS.

The subsequent authentication registration message of the first terminal is routed to the second S-CSCF and the registration fails.

In the process of implementing the present invention, the inventor finds that the above problems may occur not only in the user registration process, but also in other business processes, such as during the session, when the user is found to be unregistered but not registered. In the state of service, as shown in FIG. 3, an IMS process for controlling a called session request includes:

Step 201: The called home network I-CSCF receives the session request sent by the UE of the visited network. Step 202: After receiving the session request, the I-CSCF queries the HSS for user information through the LIR message.

Step 203: The HSS checks the user registration information and the subscription data, and finds that the user is not registered but has an unregistered service, and returns a capability set of the called home network S-CSCF to the I-CSCF through the LIA message;

Step 204: The I-CSCF selects an appropriate S-CSCF according to the S-CSCF capability set returned by the HSS, and forwards the session request to the selected S-CSCF.

Step 205: The selected S-CSCF receives the session request, and finds that the user is not registered, and requests the HSS to download the subscription data through the SAR message.

Step 206, the HSS saves the address of the selected S-CSCF, and returns the user by using the SAA message. Authentication data to the selected S-CSCF;

Finally, the selected S-CSCF saves the subscription data and processes the user session service.

In the above-mentioned prior art session, if the user is found to be unregistered but has an unregistered state, the I-CSCF selects the first S-CSCF for the first session service of the user. If the HSS processes the SAR request of the first S-CSCF, the I-CSCF processes the second session service of the user terminal, and the I-CSCF selects the second S-CSCF for the second session service, such that the second S- When the CSCF processes the second session service, the address of the second S-CSCF saved in the HSS is overwritten, and the address of the first S-CSCF is overwritten, and a network logout request is initiated to the first S-CSCF to establish the first S-CSCF. The session is released.

Therefore, whether the user registration process or the session process, when the user is not registered, the I-CSCF processes two registration requests or session requests and selects two S-CSCFs in succession, which may result in the first S-CSCF. The session is released with errors that affect the normal communication process. The same problem occurs when the I-CSCF handles more than two registration requests or session service requests. Summary of the invention

The embodiment of the invention discloses a method and a system for allocating a service call session control function, so that when a user has at least two service requests at the same time, the service call session control function can be effectively allocated for subsequent processing. Can be carried out normally.

An embodiment of the present invention provides a method for allocating a service call session control function, where the method includes:

The home subscriber server receives a request message for saving the server address sent by the query call session control function, where the message includes the service call session control function address selected by the query call session control function for the user;

The home subscriber server checks whether the service call session control function address is saved locally for the user, and if there is a save, the home subscriber server returns the saved service call session control function address to the query call session control function; if not saved And the home subscriber server saves the selected service call session control function address for the user, and returns the selected service call session control function address to the query call session control function.

The embodiment of the invention further provides a method for allocating a service call session control function, the method comprising: The home subscriber server receives a query request sent by the query call session control function according to the service request of the user;

The home subscriber server checks, according to the query request, whether the service call session control function address has been saved locally for the user, and if there is a save, returns the saved service call session control function address to the query call session control function; If not saved, the home subscriber server selects a service call session control function for the user, then saves the selected service call session control function address for the user, and returns the selected service call session control function address to the user Query the call session control function.

The embodiment of the present invention further provides a system for allocating a service call session control function, where the system includes: an inquiry call session control function, a home subscriber server;

The query call session control function is configured to send a request message for saving a server address to a home subscriber server, where the message includes a service call session control function address selected by the query call session control function for the user;

The home subscriber server is configured to receive a request message for saving a server address sent by the query call session control function, and check whether the service call session control function address is saved locally for the user, and if there is a save, return the service saved for the user. Calling the session control function address to the query call session control function; if not saved, the home subscriber server saves the selected service call session control function address, and returns the selected service call session control function address to the query call session control function .

The embodiment of the present invention further provides another system for allocating a service call session control function, where the system includes: an inquiry call session control function, a home subscriber server;

Querying a call session control function, configured to send a query request to the home subscriber server, where the request message carries capability requirement information;

The home subscriber server is configured to check whether a service call session control function address is saved locally for the user, and if there is a save, the home subscriber server is configured to return the saved service call session control function address to the query call session control. Function; if not saved, the home subscriber server is configured to select a service call session control function for the user from the service call session control function list according to the capability requirement information and the locally saved capability information, and select the selected service call The session control function address is returned to the query call session control function and saved for the user The selected service call session control function address.

The embodiment of the present invention further provides a home subscriber server, where the home subscriber server includes a storage unit, a second detecting unit, and an information interaction unit.

a storage unit, configured to save a service call session control function address information and a service call session control function capability set for the user;

The information interaction unit is configured to receive a request message for saving the server address sent by the query call session control function, where the message includes the service call session control function address selected by the query call session control function, and send the message to the second Detection unit

a second detecting unit, configured to check whether the storage unit saves the service call session control function address for the user; if there is a save, the second detecting unit is configured to return the saved service call session control function address to the information interaction unit Querying the service call session control function; if not saved, the second detecting unit is configured to return the service call session control function address selected by the query service call session control function to the query service call session control function through the information interaction unit, and The service call session control function selected by the user is saved to the storage unit.

The embodiment of the present invention further provides a home subscriber server, where the home subscriber server includes a detecting unit, a storage unit, a selecting unit, and an information interaction unit.

a storage unit, configured to save a service call session control function list and a service call session control function address information selected for the user;

An information interaction unit, configured to receive a query request sent by the query service call session control function, and forward the query request to the detecting unit;

a detecting unit, configured to: after receiving the query request sent by the information interaction unit, check whether the local service session control function address is saved for the user; if there is a save, the detecting unit is configured to pass the saved service call session control function address The information interaction unit returns to the query call session control function; if it is saved, the detecting unit is configured to return the service call session control function address selected by the selection unit to the query call session control function, and control the service call session selected for the user The function is saved to the storage unit;

And a selecting unit, configured to select a service call session control function for the user from the service call session control function list saved by the storage unit according to the capability requirement information.

In the embodiment of the present invention, the home subscriber server processes the call session control function for the user to process the service. When the request can be made, if it is found that a service call session control function address has been saved for the user, the home subscriber server no longer saves the new service call session control function address, but sends the saved service call session control function address to the query. The call session control function, if it is found that the service call session control function address is not saved for the user, after selecting a service call session control function, a process of saving the service call session control function server address is added. Therefore, when the other terminal performs the second registration request for the user equipment or when there are two session requests at the same time, the home subscriber server performs the service call session control function according to whether the service call session control function address allocated for the user is saved. Assignment, if there is a save, then continue to allocate the saved service call session control function to the second registration request or the second session request; if not, reassign and save the newly assigned service call session control function address. Therefore, there is no problem that the distribution service call session control function is overwritten, and the communication can be guaranteed to proceed normally. DRAWINGS

1 is a schematic diagram of an IMS network architecture provided by the prior art;

2 is a flow chart of a method for allocating an S-CSCF by an IMS provided by the prior art when controlling a user registration request;

3 is a flow chart of a method for allocating an S-CSCF when a IMS control user is called by a request provided by the prior art;

4 is a schematic structural diagram of a communication system according to an embodiment of the present invention;

5 is a flow chart of allocating an S-CSCF according to another embodiment of the present invention; FIG. 6 is a flow chart of allocating an S-CSCF during a session according to another embodiment of the present invention;

7 is a communication system of an IMS-assigned S-CSCF according to another embodiment of the present invention; FIG. 8 is a flow chart of allocating an S-CSCF in a registration process according to another embodiment of the present invention;

FIG. 9 is a flow chart of allocating an S-CSCF during a session according to another embodiment of the present invention. detailed description The embodiments of the present invention can be applied to various scenarios in which an S-CSCF needs to be allocated, such as a registration scenario, a session service scenario, or a message service scenario. For the convenience of description, the following embodiments are described by taking a user-initiated registration request and a user-initiated session service request process as an example.

As shown in FIG. 4, it is a schematic structural diagram of a communication system according to an embodiment of the present invention. The communication system includes: UE41, P-CSCF42 located in the visited network, and I-CSCF43, S-CSCF44, and HSS45 located in the home network.

The I-CSCF 43 may further include a selection unit 431 and an information interaction unit 432. The HSS 45 may further include a first detection unit 450, a storage unit 451, an information interaction unit 452, and a second detection unit 453.

When the application scenario initiates a registration request, the main working process of the above communication system can be as follows:

The UE 41 initiates a registration request to the P-CSCF 42; the P-CSCF 42 acquires the I-CSCF 43 address from the registration request information, and forwards the registration request to the information interaction unit 432 of the I-CSCF 43.

The information interaction unit 432 receives the registration request, and queries the HSS 45 for the registration status of the user UE 41 by using the UAR message of the registration status inquiry process.

The information interaction unit 452 of the HSS 45 receives the UAR message, and the first detecting unit 450 detects, according to the UAR message to the storage unit 451, whether the S-CSCF address allocated for the user UE 41 has been saved. If there is a save, the first detecting unit 450 notifies the information interaction unit 452 to return the allocated S-CSCF address to the I-CSCF 43 through the UAA message, and the information interaction unit 432 of the I-CSCF 43 routes the registration request to the assigned S-CSCF. . If the first detecting unit 450 checks that the user UE 41 is not saved, the first detecting unit 450 notifies the information interaction unit 452 to return the capability set of the S-CSCF to the I-CSCF 43 to the I-CSCF 43 through the UAA message.

The information interaction unit 432 of the I-CSCF 43 forwards the capability set of the S-CSCF to the selection unit 431, and the selection unit 431 selects an appropriate S-CSCF according to the capability set of the S-CSCF, such as selecting the S-CSCF 44, and then the information. The interaction unit 432 transmits the selected S-CSCF 44 address to the information interaction unit 452 of the HSS 45 by the SSR message of the server address procedure (the SSR message is a request message that holds the server address).

The information interaction unit 452 obtains the S-CSCF44 address selected by the UE 41 according to the SSR message, and then transmits the selected S-CSCF44 address to the second detecting unit 453. Second detecting unit 453 It is checked whether the S-CSCF address information is saved for the user in the storage unit 451. If there is a save, the information interaction unit 452 returns the S-CSCF address saved for the user to the I-CSCF 43 through the SSA message. If not saved, the storage unit 451 saves the selected S-CSCF 44 address, can set the corresponding user to the allocated state, and starts a protection timer; then, the information interaction unit 452 returns the selected one through the SSA. The S-CSCF 44 address is given to the I-CSCF 43.

The information interaction unit 432 uses the returned S-CSCF as the S-CSCF allocated to the user according to the returned S-CSCF address, and forwards the registration request to the S-CSCF allocated to the user.

The S-CSCF allocated to the user receives the registration request, and finds that it is the initial registration, and acquires the authentication set of the registered user from the HSS 45 through the MAR message.

The information interaction unit 452 acquires the authentication set of the registered user from the storage unit 451, updates the status of the user, stops the protection timer, and returns the user authentication data to the S-CSCF assigned to the user through the MAA message.

The S-CSCF allocated to the user selects an authentication vector, and sends a 401 message to the information interaction unit 432, where the 401 message carries the selected authentication vector; the information interaction unit 432 of the I-CSCF 43 Forwarding 401 a message to the P-CSCF 42; the P-CSCF 42 forwards a 401 message to the UE 41; the UE 41 calculates an authentication response according to an authentication vector in the 401 message, and re-initiates a registration request to the P-CSCF 42 .

The P-CSCF 42 forwards the registration request to the information interaction unit 432 of the I-CSCF 43; the information interaction unit 432 receives the registration request, and queries the HSS 45 for the registration status of the user UE41 through the UAR message.

The information interaction unit 452 of the HSS 45 receives the UAR message, the first detecting unit 450 retrieves the S-CSCF address allocated to the user according to the UAR message to the storage unit 451, and the information interaction unit 452 returns the message through the UAA message. An S-CSCF address assigned to the user to the information interaction unit 432 of the I-CSCF 43; the information interaction unit 432 forwards the registration request to the S- assigned to the user according to the S-CSCF address assigned to the user CSCF.

The S-CSCF allocated to the user detects the authentication response. If the authentication succeeds, the HSS is requested to download the subscription data through the SAR message. After receiving the request, the HSS updates the registration information of the storage unit 451 in the HSS 45 and the status of the user. Returning the user's subscription data to the S-CSCF assigned to the user;

The S-CSCF allocated to the user returns a registration success confirmation message to the I-CSCF 43; the I-CSCF 43 returns a registration success confirmation message to the P-CSCF 42; the P-CSCF 42 returns a registration success confirmation message to the User UE41 is described.

If the protection timer expires, the HSS 45 clears the saved service call session control function address from the storage unit 451.

The above communication system can be applied not only to the scenario of the registration request but also to the session service request scenario. When applied to the session service request, the main working process of the foregoing communication system may be as follows: The information interaction unit 432 of the called home network I-CSCF 43 receives the session request of the called user UE 41 from the calling network; the information interaction unit 432 The user UE41 information is queried to the HSS 45 through the LIR message of the location query procedure.

The information exchange unit of the HSS 45 receives the LIR message, and the first detecting unit 450 checks the user UE 41 registration information and the subscription data according to the LIR message to the storage unit 451, and feeds back the detection result to the information interaction unit 452. If the first detecting unit 450 finds that the user UE 41 is not registered but has an unregistered state service, in addition, if the local has saved the S-CSCF address for the user UE 41, the information interaction unit 452 returns to the I-CSCF 43 through the LIA message. The saved S-CSCF address; if the S-CSCF address is not saved locally for the user UE41, the information interaction unit 452 returns the capability set of the S-CSCF to the information interaction unit 432 of the I-CSCF 43 through the LIA message, the information The interaction unit 432 forwards the capability set of the S-CSCF to the selection unit 431.

The selection unit 431 selects an appropriate S-CSCF according to the returned S-CSCF capability set, such as selecting the S-CSCF 44, and then the information interaction unit 432 sends an SSR message to the information interaction unit 452 of the HSS 45, the SSR message carrying the selection. S-CSCF44 address.

The information interaction unit 452 acquires the selected S-CSCF address according to the SSR message, and transmits the selected S-CSCF address to the second detecting unit 454, and the second detecting unit 454 checks whether the storage unit 451 is in the storage unit 451. The user saves the S-CSCF address and feeds the detection result back to the information interaction unit 452. If the first detecting unit 450 detects that the storage unit 451 saves the S-CSCF address for the user, the information interaction unit 452 returns the saved S-CSCF address to the information interaction unit 432 of the I-CSCF 43 through the SSA message, and the selection unit 431. The returned S-CSCF address is assigned to the S-CSCF of the user. If the storage unit 451 does not save the S-CSCF address for the user, the storage unit 451 saves the selected S-CSCF44 address, sets the corresponding user to the allocated state, and starts the protection timer. The information interaction unit 452 returns the selected S-CSCF 44 address to the information interaction unit 432 via the SSA message, and the selection unit 431 uses the returned S-CSCF 44 as the S-CSCF assigned to the user.

The information interaction unit 432 forwards the session request to the S-CSCF assigned to the user. The S-CSCF allocated to the user receives the session request, and finds that the user UE41 is not registered, requests the storage unit 451 of the HSS 45 to download the subscription data through the SAR message, and the HSS 45 updates the user status and stops the protection timer. The information interaction unit 452 then acquires the subscription data of the user UE 41 from the storage unit 451 and returns the subscription data of the user UE 41 to the S-CSCF assigned to the user through the SAA message.

The S-CSCF allocated to the user saves subscription data and processes user session services. If the protection timer expires, the HSS 45 may clear the saved service call session control function address from the storage unit 451.

In the above embodiment, after the I-CSCF 43 selects an S-CSCF, a process of saving the server address (Save-Server Name-Request/Answer, SSR/SSA) is added, and if the HSS 45 processes the S-CSCF request, if found The S-CSCF address has been saved for the user, and the storage unit 451 of the HSS 45 no longer saves the new S-CSCF address, but sends the saved S-CSCF address to the I-CSCF 43 so that it can avoid another terminal pair. When the user UE 41 performs the second registration request or has two session requests at the same time, the HSS 45 may perform the S-CSCF allocation according to whether the allocated S-CSCF address is saved, and if there is a save, the second registration request or the second session is given. The request continues to allocate the saved S-CSCF; if not saved, the newly assigned S-CSCF address is saved. Therefore, there is no problem that the S-CSCF address coverage is confusing, and communication can be guaranteed to proceed normally.

As shown in FIG. 5, a flow chart of allocating an S-CSCF according to another embodiment of the present invention is shown. When the application scenario initiates a registration request for a user, the specific implementation process of the embodiment mainly includes:

Step 301: The UE located in the visited network initiates a registration request to the P-CSCF of the visited network. Step 302: The P-CSCF obtains an I-CSCF address of the user home network from the registration request information, and forwards the registration request to the I- CSCF;

Step 303a, the I-CSCF receives a registration request, and initiates a user registration status query request to the HSS of the home network by using the UAR message. Step 303b: After receiving the UAR message, the HSS checks whether it has saved the allocated S-CSCF address for the user UE. If there is a save, the HSS returns the saved S-CSCF address to the user through the UAA message, and the I-CSCF routes the registration request to the saved S-CSCF. If not saved, the HSS returns the capability set of the home network S-CSCF to the I-CSCF through the UAA message.

Step 304a, the I-CSCF selects an appropriate S-CSCF according to the capability set of the S-CSCF, and sends the selected S-CSCF address to the HSS through an SSR message;

Step 304b, after the HSS obtains the selected S-CSCF address according to the SSR message, it checks whether the local saves the S-CSCF address for the user, and if it has been saved, the HSS returns the saved S- through the SSA. The CSCF address is given to the I-CSCF.

If not saved, the HSS saves the selected S-CSCF address, sets the corresponding user to the allocated state, starts the protection timer, and returns the selected S-CSCF address to the I-CSCF through the SSA;

Step 305: The I-CSCF uses the returned S-CSCF as an S-CSCF allocated to the user UE according to the S-CSCF address returned by the HSS, and forwards the registration request to the user UE. S-CSCF;

Step 306: The S-CSCF allocated to the user UE receives the registration request, and finds that it is the initial registration, and obtains the authentication set of the registered user by using the MAR message to the HSS.

Step 307: The HSS returns user authentication data to the S-CSCF allocated to the user UE by using a MAA message, and updates the status of the user, and stops the protection timer.

Step 308, the allocated S-CSCF selects an authentication vector, and sends a 401 message to the I-CSCF for authentication, where the 401 message carries the selected authentication vector;

Step 309, the I-CSCF forwards a 401 message to the P-CSCF;

Step 310: The P-CSCF forwards a 401 message to the UE.

Step 311: The UE calculates an authentication response according to an authentication vector in the 401 message, and re-initiates a registration request to the P-CSCF.

Step 312, the P-CSCF forwards the registration request to the I-CSCF;

Step 313: The I-CSCF receives the registration request, and queries the HSS to query the user registration status by using a UAR message. Step 314, the HSS checks the user registration status, and if the HSS has saved the S-CSCF address allocated to the user UE for the user, returns the S-CSCF address allocated to the user UE through the UAA message. Giving the I-CSCF;

Step 315: The I-CSCF forwards a registration request to the S-CSCF allocated to the user UE according to the S-CSCF address allocated to the user UE.

Step 316: The S-CSCF allocated to the user UE checks the authentication response. If the authentication succeeds, the SAR message is used to request the HSS to download the user subscription information.

Step 317: The HSS updates the registration information and the user status of the user, and returns the subscription data of the user to the S-CSCF allocated to the user UE by using the SAA message.

Step 318, the S-CSCF allocated to the user UE returns a registration success confirmation message to the I-CSCF;

Step 319, the I-CSCF returns a registration success confirmation message to the P-CSCF;

Step 320: The P-CSCF returns a registration success confirmation message to the UE.

In the above embodiment, after the I-CSCF selects an S-CSCF, a process of saving the S-CSCF address is added to save the selected S-CSCF address to the HSS, and the process is in the user registration status query process (step 303b) After. Then, when the HSS processes the SSR request, if it is found that the S-CSCF address has been saved for the user, the HSS brings the saved S-CSCF address to the I-CSCF in the response message SSA message, so When a terminal makes a second registration request to the user, the HSS performs S-CSCF allocation according to whether the S-CSCF address allocated to the user is saved, and if it is saved, the second registration request is continued to allocate the saved S-. CSCF; If not, reassign and save the newly assigned S-CSCF address. Therefore, the problem that the S-CSCF address coverage is disordered is not generated, and the communication can be guaranteed to proceed normally.

The embodiment of the present invention can be applied not only in the process of initiating a registration request by a user, but also in other scenarios in which an S-CSCF needs to be allocated, for example, in a session service request process.

As shown in FIG. 6 , a flow chart of allocating an S-CSCF in a session process according to another embodiment of the present invention, where the application scenario is that a user initiates a session request, the specific implementation process of the embodiment includes:

Step 401: The called home network I-CSCF receives the session request of the called user UE from the calling network. Step 402a, the I-CSCF queries the HSS for user information by using the LIR message.

Step 402b, the HSS checks user registration information and subscription data, and finds that the user is not registered but If there is an unregistered state service, if the local has saved the S-CSCF address for the user UE, the HSS returns the saved S-CSCF address to the I-CSCF through the LIA message; The user UE saves the S-CSCF address, and the HSS returns the called home network S-CSCF capability set to the I-CSCF through the LIA message;

Step 403a, the I-CSCF selects an appropriate S-CSCF according to the S-CSCF capability set returned by the HSS, and sends the selected S-CSCF address to the HSS through an SSR message;

Step 403b: After obtaining the selected S-CSCF address according to the SSR message, the HSS checks the locally saved S-CSCF address information. If the local has saved the S-CSCF address for the user, the HSS saves the saved S- The CSCF address is returned to the I-CSCF through the SSA message; if not saved locally, the selected S-CSCF address is saved, the user is placed in the allocated state, the protection timer is started, and the selected S-CSCF address is set. Return to the I-CSCF through the SSA message;

Step 404, the I-CSCF uses the S-CSCF address returned by the HSS as the S-CSCF allocated to the user UE, and forwards the request to the S-CSCF allocated to the user UE;

Step 405: The S-CSCF allocated to the user UE receives the session request, and finds that the user is not registered, and requests the HSS to download the subscription data through the SAR message.

Step 406, the HSS updates the state of the user, stops the protection timer, and returns the user subscription data to the S-CSCF allocated to the user UE through the SAA message;

Finally, the S-CSCF allocated to the user UE saves the subscription data and processes the user session service. In the above embodiment, after the I-CSCF selects an S-CSCF, a process of saving the S-CSCF address is added for saving the selected S-CSCF address to the HSS, and the process is in the user location query process (step 402b). )after that. Then, when the HSS processes the session request, if it is found that the S-CSCF address has been saved for the user, the HSS no longer saves the new S-CSCF address, but brings the saved S-CSCF address to the I-CSCF, so It can be avoided that when another terminal makes a second session request to the user, the HSS performs S-CSCF allocation according to whether the S-CSCF address allocated to the user is saved, and if there is a save, the second session request is continued to allocate the already Saved S-CSCF; if not, reassign and save the newly assigned S-CSCF address. Therefore, the problem that the S-CSCF address coverage is disordered is not generated, and the communication can be guaranteed to proceed normally.

Another embodiment of the present invention provides another communication system for allocating an S-CSCF. In this embodiment, the S-CSCF is selected and saved by the HSS. Specifically, as shown in FIG. 7, the communication system includes: The UE 71 and the P-CSCF 72 located in the visited network are located at the I-CSCF 73, the S-CSCF 74, and the HSS 75 of the home network.

The HSS 75 further includes a detecting unit 750, a storage unit 751, a selecting unit 752, and an information interaction unit 753.

The working process of this embodiment is basically similar to the embodiment shown in FIG. 4, except that in this embodiment, the S-CSCF is selected to be performed in the HSS, as described below. When the application scenario initiates a registration request by the user, the foregoing The main working process of the communication system can be as follows:

The UE 71 initiates a registration request to the P-CSCF 72; the P-CSCF 72 obtains the I-CSCF 73 address of the user's home network from the registration request information, and forwards the registration request to the I-CSCF 73.

The I-CSCF 73 receives the registration request, and initiates a query request to the HSS 75 by using the UAR message, where the query request carries related capability requirement information, where the related capability requirement information specifically includes the capability information of the S-CSCF and/or the availability of the S-CSCF. Information and/or network topology information, but is not limited to this information.

The information interaction unit 753 of the HSS 75 receives the UAR message, and the detecting unit 750 detects, according to the UAR message, to the storage unit 751 whether the S-CSCF address has been saved for the user.

If the detecting unit 750 detects that the S-CSCF address has been saved locally for the user, the detecting unit 750 notifies the information interaction unit 753 to return the saved S-CSCF address to the I-CSCF 73 through the UAA message (for example, the S-CSCF 74). Address), I-CSCF73 routes the registration request to the saved S-CSCF 74.

If the detecting unit 750 checks that the S-CSCF address is not saved locally for the user, the selecting unit 752 is configured from the saved S-CSCF list according to the capability requirement information carried by the UAR and the locally saved S-CSCF capability information. Select a suitable S-CSCF, such as S-CSCF74. The storage unit 751 saves the selected S-CSCF 74 address for the user, sets the user to an allocated state, and starts a protection timer. Then, the selecting unit 752 passes the selected S-CSCF 74 address to the information interaction unit 753, and the information interaction unit 753 returns the selected S-CSCF 74 address to the I-CSCF 73 through the UAA message.

The I-CSCF 73 forwards the registration request to the selected S-CSCF 74 according to the selected S-CSCF 74 address returned by the UAA message, and the selected S-CSCF 74 receives the registration request, and finds that it is the initial registration, and then passes The MAR message acquires the authentication set of the registered user from the HSS 75.

After receiving the MAR message, the information interaction unit 753 acquires the registered user from the storage unit 751. The authentication set updates the status of the user, stops the protection timer, and returns user authentication data to the S-CSCF 74 through the MAA message.

The S-CSCF 74 selects an authentication vector, and sends a 401 message to the I-CSCF 73, where the 401 message carries the selected authentication vector; the I-CSCF 73 forwards the 401 message to the P-CSCF 72; The P-CSCF 72 forwards the 401 message to the UE 71; the UE 71 calculates an authentication response according to the authentication vector in the 401 message, and re-initiates the registration request to the P-CSCF 72.

The P-CSCF 72 forwards the registration request to the I-CSCF 73, and the I-CSCF 73 queries the HSS 75 for the registration status of the user UE 71 through the UAR message.

The HSS 75 checks the user registration status. If the storage unit 751 of the HSS 75 has saved the S-CSCF address for the user, the information interaction unit 753 returns the saved S-CSCF address to the I-CSCF 73 through the UAA message.

The I-CSCF 73 uses the returned S-CSCF as an S-CSCF allocated to the user UE 71 according to the returned S-CSCF address, and forwards the registration request to the S-CSCF allocated to the user UE 71.

The S-CSCF allocated to the user UE 71 checks the authentication response. If the authentication succeeds, the S-CSCF allocated to the user UE 71 requests the HSS 75 to download the user subscription data through the SAR message.

The HSS 75 updates the user registration information of the storage unit 751 in the HSS 75. The information interaction unit 753 acquires the subscription data of the user UE 71 from the storage unit 751 and returns the subscription data of the user UE 71 to the S- allocated to the user UE 71 through the SAA message. CSCF;

The S-CSCF allocated to the user UE 71 returns a registration success confirmation message to the I-CSCF 73; the I-CSCF 73 returns a registration success confirmation message to the P-CSCF 72; the P-CSCF 72 returns a registration success confirmation message to The user UE71.

If the protection timer expires, the HSS 75 clears the saved service call session control function address from the storage unit 751.

The above description is the working process of the communication system when the user initiates the registration request service. When the above communication system is applied to the user to initiate the session service request, the main working process can be as follows:

The I-CSCF 73 of the home network receives the session request sent by the UE 71 of the visited network, and the I-CSCF 73 queries the HSS 75 for the user information through the LIR message, and the LIR message carries the relevant capability requirement information. The capability requirement information specifically includes, but is not limited to, capability information of the S-CSCF and/or availability information of the S-CSCF and/or network topology information. The information interaction unit 753 of the HSS 75 receives the LIR message, and transmits the LIR message to the detecting unit 750. The detecting unit 750 checks the user registration information and the subscription data according to the LIR message to the storage unit 751, and feeds back the detection result to the information. Interaction unit 753.

If the detecting unit 750 finds that the user UE 71 is not registered but has an unregistered state service, and the detecting unit 750 detects that the storage unit 751 has saved the S-CSCF address (for example, the S-CSCF 74 address) for the user UE 71, the information interaction unit 753 returns the S-CSCF 74 address to the I-CSCF 73 through the LIA message; if the detecting unit 750 finds that the user UE 71 is not registered but has an unregistered state service, in addition, the detecting unit 750 detects that the storage unit 751 is not saved as the S allocated by the user UE 71. The -CSCF address, the selection unit 752 selects an appropriate S-CSCF from the list of S-CSCFs held by the storage unit 751 based on the capability requirement information carried by the LIR and the locally saved S-CSCF capability information, for example, selecting the S-CSCF 74. Then, the storage unit 751 saves the S-CSCF74 address for the user UE71, sets the corresponding user identifier to an allocated state, and starts a protection timer, and then the information interaction unit 753 sends the I-CSCF 73 through the LIA message. Returns the selected S-CSCF 74 address.

The I-CSCF 73 assigns the returned S-CSCF to the S-CSCF of the user UE 71 according to the S-CSCF address returned by the LIA message, and forwards the session request to the S-CSCF allocated to the user UE 71.

The S-CSCF allocated to the user UE 71 receives the session request, and finds that the user is not registered, and requests the HSS 75 to download the subscription data through the SAR message.

The HSS 75 updates the status of the user, stops the protection timer, and returns the user subscription data to the assigned S-CSCF through the SAA message.

Finally, the S-CSCF 74 saves the subscription data and processes the user session service.

As shown in FIG. 8 , a flow chart of allocating an S-CSCF in a registration process according to another embodiment of the present invention, where an application scenario is a user requesting a registration request, the specific implementation process of the embodiment includes:

Step 501: The UE initiates a registration request to the P-CSCF.

Step 502: The P-CSCF obtains an I-CSCF address of the user home network from the registration request information, and forwards the registration request to the I-CSCF.

Step 503: The I-CSCF receives the registration request, and queries the HSS of the home network to query the user registration status by using the UAR message, where the UAR message carries related capability requirement information.

Step 504: The HSS checks whether there is an S-CSCF address saved for the user UE locally. If there is a save, the HSS returns the saved S-CSCF address to the I-CSCF, and the I-CSCF routing note Request for the saved S-CSCF.

If not saved, the HSS selects an appropriate S-CSCF from the locally saved S-CSCF list according to the capability requirement information carried by the UAR and the locally saved S-CSCF capability information. The HSS saves the selected S-CSCF address, sets the corresponding user to the allocated state, and starts a protection timer, and then the HSS returns the selected S-CSCF address to the I-CSCF through the UAA message;

Step 505: The I-CSCF forwards the registration request to the allocated S-CSCF according to the S-CSCF address returned by the UAR, and uses the S-CSCF as the allocated S-CSCF.

Step 506: The allocated S-CSCF receives the registration request, and finds that it is the initial registration, and obtains the authentication set of the registered user by using the MAR to the HSS.

Step 507: The HSS updates the status of the corresponding user, stops the protection timer, and returns the user authentication data to the allocated S-CSCF by using the MAA message.

Step 508, the allocated S-CSCF selects an authentication vector, and sends a 401 message to the I-CSCF for authentication, where the 401 message carries the selected authentication vector;

Step 509, the I-CSCF forwards a 401 message to the P-CSCF;

Step 510, the P-CSCF forwards 401 a message to the user UE;

Step 511: The UE calculates an authentication response according to an authentication vector in the 401 message, and re-initiates a registration request to the P-CSCF.

Step 512, the P-CSCF forwards the registration request to the I-CSCF;

Step 513: The I-CSCF receives the registration request, and queries the HSS to query the user registration status by using a UAR message.

Step 514, the HSS checks the user registration status, and if the HSS has saved the S-CSCF address for the user, returns the allocated S-CSCF address to the I-CSCF through the UAA message; Step 515, The I-CSCF forwards the registration request to the allocated S-CSCF according to the allocated S-CSCF address;

Step 516, the allocated S-CSCF detects an authentication response, and if the authentication succeeds, sends a SAR message to the HSS, requesting to download the subscription data of the user;

Step 517: The HSS updates the registration information of the user, and returns the subscription data of the user to the allocated S-CSCF by using the SAA message.

Step 518, the allocated S-CSCF returns a registration success confirmation message to the I-CSCF; Step 519: The I-CSCF returns a registration success confirmation message to the P-CSCF. Step 520: The P-CSCF returns a registration success confirmation message to the UE.

The embodiment of the present invention can be applied not only in the registration request process but also in other scenarios where the S-CSCF needs to be allocated, such as in the session service request process.

As shown in FIG. 9 , a flow chart of the S-CSCF is allocated to a session process according to another sixth embodiment of the present invention. When the application scenario is that the user initiates a session service request, the specific implementation process of the embodiment includes: Step 601: The called home network I-CSCF receives the session request sent by the UE of the visited network. Step 602: The I-CSCF queries the HSS for the user information by using the LIR message, where the LIR message carries related capability requirement information.

Step 603: The HSS receives the LIR message, checks user registration information and subscription data, and finds that the user is not registered but has an unregistered service, and the HSS has saved the S-CSCF address for the user, and the HSS will The saved S-CSCF address is returned to the I-CSCF through the LIA message. If the HSS check does not save the S-CSCF address for the user, the HSS selects an appropriate S- from its locally saved S-CSCF list according to the capability requirement information carried by the LIR and the locally saved S-CSCF capability information. CSCF. The HSS saves the selected S-CSCF address for the user, sets the corresponding user to the allocated state, and starts the protection timer, and then returns the selected S-CSCF address to the I-CSCF through the LIA message;

Step 604, the I-CSCF forwards the session request to the S-CSCF allocated to the user UE according to the S-CSCF address returned by the LIA message, and the S-CSCF as the S-CSCF allocated to the user UE;

Step 605, the S-CSCF allocated to the user UE receives the session request, and finds that the user is not registered, and requests the HSS to download the subscription data through the SAR message, where the SAR message carries the allocated S-CSCF address;

Step 606, the HSS updates the state of the user, stops the protection timer, and returns the user subscription data to the S-CSCF allocated to the user UE through the SAA message;

Finally, the S-CSCF allocated to the user UE saves the subscription data and processes the user session service. It can be seen from the specific implementation process of the foregoing embodiment of the present invention that, in the embodiment of the present invention, when the HSS requests the user to allocate an S-CSCF, if the S-CSCF address is found to be saved for the user, the HSS does not save the new one. The S-CSCF address is sent to the I-CSCF. If it is found that the S-CSCF address is not saved for the user, after adding an S-CSCF, add one. The process of saving the address of the S-CSCF server. Therefore, when the other terminal makes a second registration request to the user UE or has two session requests at the same time, the HSS performs S-CSCF allocation according to whether the S-CSCF address allocated for the user is saved, and if there is a save, Then, the second registration request or the second session request is continued to allocate the saved S-CSCF; if not, the newly allocated S-CSCF address is re-allocated and saved. Therefore, there is no problem that the allocation S-CSCF coverage is disordered, and communication can be guaranteed to proceed normally.

A person skilled in the art can understand that all or part of the steps of implementing the foregoing embodiments can be completed by a program instructing related hardware, and the program can be stored in a computer readable storage medium, the storage. Media, such as: ROM/RAM, disk, CD, etc.

However, the above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any person skilled in the art will recognize that any and all that is within the spirit and scope of the present invention Modifications, equivalent substitutions, improvements, etc., are intended to be included within the scope of the invention.

Claims

Rights request

A method for allocating a service call session control function, comprising the steps of:

2. The method of claim 1, wherein the method further comprises:

After receiving the service request of the user, the query call session control function sends a query request to the home subscriber server;

If the home subscriber server checks, according to the query request, that the service call session control function address is not saved locally for the user, the home subscriber server returns a capability set of the service call session control function to the query call session control function;

The service call session control function selected by the query call session control function for the user is specifically that the query call session control function selects a service call session control function selected by the user according to the capability set of the service call session control function.

3. The method according to claim 1, wherein after the home subscriber server saves the selected service call session control function address for the user, the method further includes setting the user to an allocated state. .

A method for allocating a service call session control function, the method comprising: the home subscriber server receiving a query request sent by the query call session control function according to a service request of the user;

The home subscriber server checks, according to the query request, whether the service call session control function address has been saved locally for the user, and if there is a save, the saved service call session control The function address is returned to the query call session control function; if not saved, the home subscriber server selects a service call session control function for the user, and then saves the selected service call session control function address for the user, and The selected service call session control function address is returned to the inquiry call session control function.

The method according to claim 4, wherein the home subscriber server has the capability requirement information carried in the query request sent by the query call session control function, and the locally saved service call session control function capability. Information, select a service call session control function for the user.

The method according to claim 4, wherein after the home subscriber server saves the selected service call session control function address for the user, the method further includes setting the user to an allocated state. .

7. A communication system for assigning a service call session control function, the communication system comprising: an inquiry call session control function, a home subscriber server;

8. The communication system according to claim 7, wherein said inquiry call session control function further comprises a selection unit for selecting a service call session control function according to a capability set of the service call session control function.

The communication system according to claim 8, wherein the home subscriber server further comprises a storage unit, a second detecting unit, and an information interaction unit;

a storage unit, configured to save a service call session control function address information and a service call session control function capability set for the user; The information interaction unit is configured to receive a request message for saving the server address sent by the query call session control function, where the message includes the service call session control function address selected by the query call session control function, and send the message Giving a second detection unit;

a second detecting unit, configured to check whether the storage unit saves the service call session control function address for the user; if there is a save, the second detecting unit is configured to return the saved service call session control function address to the query through the information interaction unit The service call session control function; if not saved, the second detecting unit is configured to return the service call session control function address selected by the query service call session control function to the query service call session control function through the information interaction unit, and will be the user The selected service call session control function is saved to the storage unit.

10. The communication system according to claim 9, wherein the home server further comprises:

a first detecting unit, configured to check, according to a query request sent by the query service call session control function, to the storage unit to check whether a service call session control function address is saved for the user, and if there is a save, the saved service call session control function address is saved. Returning to the query service call session control function by the information interaction unit; if not saved, returning the capability set of the service call session control function to the query service call session control function through the information interaction unit.

11. A communication system for assigning a service call session control function, the communication system comprising: an inquiry call session control function, a home subscriber server;

The home subscriber server is configured to check whether a service call session control function address is saved locally for the user, and if there is a save, the home subscriber server is configured to return the saved service call session control function address to the query call session control. Function; if not saved, the home subscriber server is configured to select a service call session control function for the user from the service call session control function list according to the capability requirement information and the locally saved capability information, and select the selected service call The session control function address is returned to the inquiry call session control function, and the selected service call session control function address is saved for the user.

The communication system according to claim 11, wherein the home subscriber server further comprises a storage unit, an information interaction unit, a detection unit, and a selection unit; a storage unit, configured to save a service call session control function list and a service call session control function address information selected for the user;

a selecting unit, configured to select a service call session control function for the user from the service call session control function list saved by the storage unit according to the capability requirement information;

a detecting unit, configured to: after receiving the query request sent by the information interaction unit, check whether the local service session control function address is saved for the user; if there is a save, the detecting unit is configured to pass the saved service call session control function address The information interaction unit returns to the query call session control function; if not saved, the detecting unit is configured to return the service call session control function address selected by the selection unit to the query call session control function, and control the service call session selected for the user The function is saved to the storage unit.

A home subscriber server, wherein the home subscriber server includes a storage unit, a second detecting unit, and an information interaction unit;

The home subscriber server according to claim 13, wherein the home subscriber server further comprises:

a first detecting unit, configured to check, according to a query request sent by the query service call session control function, to the storage unit to check whether a service call session control function address is saved for the user, if there is a save, And returning the saved service call session control function address to the query service call session control function by using the information interaction unit; if not, returning the service call session control function capability set to the query service call session control by using the information interaction unit Features.

A home subscriber server, wherein the home subscriber server comprises a storage unit, an information interaction unit, a detection unit, and a selection unit;