WO2008080297A1 - A method, equipment and system for relating the session - Google Patents

Abstract

A method, equipment and system for relating the session are used to solve the problem that the first session and the second session which is required to be related could not be related in the prior art. The method includes: when the CSI terminal processes the first session, it generates an identifier corresponding to the first session, and the identifier is carried in the message sent when the first session is processed and in the message of the second session created later relating to the first session; after receiving the message, the CSI intercommunication function entity identifies the identifier carried in the message and matches it with the stored local identifier, if the matching is failed, it is determined that the received message belongs to the first session, then the identifier carried in the message is stored and the corresponding relation between the identifier and the first session is recorded; if the matching is successful, it is determined that the received message belongs to the second session, then the first session and the second session are related. The invention also provides a method for transferring the relating session information.

Description

 Method, device and system for associating conversation

Technical field

 The present invention relates to the field of communications, and in particular, to a method, apparatus, and system for associating a session, and a method for communicating associated session information. Background technique

 IMS (IP Multimedia Subsystem, IP Multimedia Subsystem) is an IP Multimedia Subsystem in the WCDMA (Wide-Band Code Division Multiple Access) network defined by the 3GPP R5/R6 standard, which is implemented by 3G mobile network. Packet voice and packet data, providing a unified network of multimedia services and applications. The IMS uses the IP packet domain as the bearer channel for its control signaling and media transmission, and uses the SIP (Session Initiation Protocol) protocol as the call control signaling. In IMS, the IMS user subscription data is centrally managed in the HSS, and the service is uniformly provided by the application server AS. The session control is completed by the S-CSCF (Serving Call Session Control Function), and the two are completely separated in the network structure, and the service passes through S. -CSCF triggers to AS processing, and multiple ASs can work together. The user accesses the IMS through the current local proxy node P-CSCF (Proxy Call Session Control Function), and the session and service control are completed by the home domain service node of the registered place, so the user can always obtain the same service at different access points. It realizes the separation of service management, session control and bearer access, and service provision independent of access and location.

 CSI (Combined CS Bearers with IMS) is a research topic in the current 3GPP standards. This topic focuses on how to combine 3G CS (Circuit Switched) domain services with IMS domain services.

In the implementation of the CSI terminal and the IMS terminal interoperability, the existing standards only provide interoperable architecture and processes. Wherein, the CSI terminal acts as the calling party, and when the IMS terminal acts as the called party, the interworking is controlled in the architecture of the calling network, as shown in FIG. 1; the interworking is controlled in the architecture of the called network, as shown in FIG. 2 . In the above two architecture diagrams, the voice session initiated by the terminal UE 1 is routed to the CSI AS, the same For example, the IMS session initiated by the terminal UE 1 is also routed to the CSI AS, and the CSI AS merges the two sessions into one, and then performs session exchange with the called terminal UE 2 by using a standard IMS procedure.

 Based on the above architecture, the CSI terminal acts as a calling party, and adds a voice call flow to the existing IMS session. As shown in FIG. 3, the following steps are included:

 1. The terminal UE 1 initiates an MSRP (Message Session Relay Protocol) session request INVITE message to the terminal UE 2.

 2. The calling network S-CSCF1 forwards the INVITE request to CSI AS1 based on iFC.

 3. The CSI AS 1 initiates a RE-INVITE request to the terminal UE2, and the request adds MSRP media to the original media.

 4. The RE-INVITE request arrives at S-CSCF2 along the initial session path.

 5. The S-CSCF2 forwards the RE-INVITE request to the terminal UE2.

 6. The terminal UE2 sends a 200 OK response message.

 7. S-CSCF2 forwards 200 OK to S-CSCF1.

 8. S-CSCF1 forwards 200 OK to CSI AS1.

 9. The CSI AS generates a 200 OK response message for the MSRP session request and sends it to the S-CSCF1.

10. The S-CSCF1 forwards the 200 OK response message to the terminal UE1.

 After that, the user's MSRP media is successfully established.

 The inventor finds in the process of the invention that the prior art only provides the architecture and process for interworking between the CSI terminal and the IMS terminal, but in a specific implementation, how does the CSI interworking function entity receive the first session when receiving the second session? The second session that needs to be associated is associated, and the related content is not disclosed in the prior art.

 Moreover, the prior art also does not provide a way of communicating the associated session information. Summary of the invention

The embodiment of the invention provides a method, a device and a system for associating a session, which are used to solve the problem that the first session and the second session to be associated are not associated with each other, so that the CSI terminal and the IMS terminal cannot communicate with each other. The embodiment of the present invention further provides a method for transmitting association session information, which is used to solve the problem that the prior art does not provide a delivery manner of associated session information.

 The method for associating a session in the embodiment of the present invention includes the following steps: generating, by the CSI terminal, an identifier corresponding to the first session when processing the first session, and sending a message in the first session, and subsequently initiating the first session The message of the associated second session carries the identifier. After receiving the message sent by the CSI terminal, the CSI interworking function entity identifies the identifier carried in the message and matches the locally saved identifier. If the matching fails, the C300 determines whether the matching is successful. Receiving the message belongs to the first session, storing the identifier carried in the message, and recording the correspondence between the identifier and the first session; if the matching is successful, determining that the received message belongs to the second session And associating the first session with a second session.

 The CSI terminal of the embodiment of the present invention includes: an identifier generating unit, configured to generate an identifier corresponding to the first session when the CSI terminal processes the first session; and a transmitting unit, configured to send a message in the first session And carrying the identifier generated by the identifier generating unit in the subsequently initiated message of the second session associated with the first session, to deliver the identifier to the network side.

 The CSI interworking function entity of the embodiment of the present invention includes: an identifying unit, configured to identify an identifier carried in a message sent by the CSI terminal, and a matching unit, configured to match the identifier identified by the identifying unit with the identifier saved by the identifier holding unit If the matching fails, determining that the received message belongs to the first session, and issuing a related indication to the identifier holding unit; if the matching is successful, determining that the received message belongs to the second session associated with the first session, and The association unit sends a relevant indication; the identifier holding unit is configured to save the identifier identified by the identification unit according to the indication of the matching unit, and record the correspondence between the identifier and the first session; and the association unit is configured to: according to the indication of the matching unit, The first session is associated with a second session.

The system for associating a session in the embodiment of the present invention includes: a CSI terminal, configured to generate an identifier corresponding to the first session when processing the first session, and send a message in the first session, and subsequently initiate the The message of the second session associated with the first session carries the identifier; the CSI interworking function entity is configured to: after receiving the message sent by the CSI terminal, identify the identifier carried in the message, and match the locally saved identifier. If the matching fails, determining that the received message belongs to the first session, saving the identifier carried in the message, and recording the correspondence between the identifier and the first session; If the match is successful, it is determined that the received message belongs to the second session, and the first session is associated with the second session.

 The method for transmitting the associated session information in the embodiment of the present invention is applied to the session association between the CSI terminal and the IMS terminal, and includes the following steps: the CSI terminal or the CSI interworking function entity carries the associated session information in the message exchanged with the peer end; After receiving the message, the terminal identifies and saves the associated session information from the message.

 In the method for associating a session in the embodiment of the present invention, the CSI terminal generates an identifier corresponding to the first session when the first session is processed, and sends a message in the first session, and a subsequent association with the first session. The message of the second session carries the identifier. After receiving the message sent by the CSI terminal, the CSI interworking function entity identifies the identifier carried in the message and matches the locally saved identifier. If the matching fails, the received information is determined. The message belongs to the first session, saves the identifier carried in the message, and records the correspondence between the identifier and the first session; if the matching is successful, it determines that the received message belongs to the second session, and The first session is associated with a second session. Thereby achieving

The CSI terminal is interworking with the IMS terminal. Embodiments of the present invention also provide apparatus and systems accordingly.

 The method for transmitting the associated session information in the embodiment of the present invention provides a specific delivery manner of the associated session information (identification), that is, the UUI of the CS message that is exchanged between the CSI terminal and the CSI interworking function entity in the CS session (User to The user information carries the associated session information. In the IMS session, the associated session information is carried in the header field of the IMS message exchanged between the CSI terminal and the CSI interworking function entity. DRAWINGS

 FIG. 1 is a schematic structural diagram of interworking control in a calling network in a case where a CSI terminal is used as a calling party and an IMS terminal is called as a called party;

 2 is a schematic structural diagram of interworking control in a called network in the case where a CSI terminal is used as a calling party and an IMS terminal is called as a called party in the prior art;

3 is a flow chart of adding a voice call to an existing IMS session by using a CSI terminal as a calling party in the prior art; 4 is a flow chart of steps of a method for associating a session according to an embodiment of the present invention;

 FIG. 5 is a signaling flowchart of Embodiment 1 of a method for associating a session according to the present invention;

 6 is a signaling flowchart of Embodiment 2 of a method for associating a session according to the present invention;

 7 is a signaling flowchart of Embodiment 3 of a method for associating a session according to the present invention;

 8 is a schematic structural diagram of a CSI terminal according to an embodiment of the present invention;

 FIG. 9 is a schematic structural diagram of a CSI interworking function entity according to an embodiment of the present invention;

 FIG. 10 is a schematic structural diagram of a system for associating a session according to an embodiment of the present invention. detailed description

 In order to associate the first session with the second session that needs to be associated, the CSI terminal communicates with the IMS terminal.

 An embodiment of the present invention provides a method for associating a session, as shown in FIG. 4, including the following main steps:

 The Sl and the CSI terminal generate an identifier corresponding to the first session when processing the first session.

 Before the CSI terminal generates the identifier corresponding to the first session, the related information may be obtained. For example, the CSI terminal obtains the CS domain MSISDN (Mobile Station International ISDN Number) of the peer from the existing field or the extended field of the first session related message. The mobile station international ISDN number), or the other way (for example, through the locally stored data) to obtain the peer domain's CS domain MSISDN number; for example: the CSI terminal obtains the PMI (Personal Mobile Information) information from the local end. Or directly use the random number as the identifier.

 The timing at which the CSI terminal generates an identifier uniquely corresponding to the first session, including but not limited to: when the CSI terminal initiates the first session; or after the first session is started, before the second session is initiated.

 The manner in which the CSI terminal generates the identifier includes one of the following:

 The CSI terminal obtains the CS domain MSISDN number of the peer end, and uses the MSISDN number as the identifier.

 The CSI terminal uses the local PMI information as the identifier.

The CSI terminal uses the random number uniquely corresponding to the first session as the identifier. The CSI terminal acquires the CS domain MSISDN number of the opposite end, and combines the MSISDN number with the random number as the identifier. For example, if the peer domain's CS domain MSISDN number is 13901391234, the identifier is 13901391234006.

 The CSI terminal combines the PMI information of the local end with the random number as the identifier. For example, if the PMI value of the CSI terminal is 0007, the identifier is 0007003.

 S2. The CSI terminal carries the identifier in an associated session message sent to the network side.

 In order to implement the interworking between the CSI terminal and the IMS terminal, the CSI terminal needs to carry the identifier in the message sent when the first session is processed, and in the message of the second session associated with the first session.

 Specifically, the CSI terminal transmits the identifier to the network side in one of the following ways:

 In the CS session, the identifier is carried in the UUI information of the CS message sent to the network side. In the IMS session, the identifier is carried in an existing header field or a newly added header field of an IMS message sent to the network side. For example, the IMS message is an IMS request message, and the identifier is carried in the user agent header field or carried in the P-Asserted-Identity header field; if the IMS message is an IMS response message, the identifier is carried in In the Server header field; or in the P-Asserted-Identity header field.

 The S3 and the CSI interworking function entity identify the identifier carried in the received message.

 After receiving the message, the CSI interworking function entity identifies the identifier carried in the message according to the type of the message and the location of the identifier carried in step S2.

 54. The CSI interworking function entity matches the identified identifier with the locally saved identifier. If the matching fails, the process proceeds to step S5. If the matching is successful, the process proceeds to step S6.

 55. Save the identifier carried in the message, and record the correspondence between the identifier and the first session. Determining that the received message belongs to the first session, and the identifier carried in the message needs to be saved, and the corresponding relationship between the identifier and the first session is recorded, so that when the second session associated with the first session arrives, the completion is completed. Match and associate operations.

 56. Complete the association.

Determining that the received message belongs to the second session, and according to the recorded identifier and the first meeting Corresponding relationship, the first session is associated with the second session.

 The method for associating a session in the embodiment of the present invention is specifically described below through three method embodiments.

 Method Embodiment 1. The CS between the CSI terminal and the IMS terminal is established first, and the session association process established after the IMS. Referring to Figure 5, the following specific steps are included:

 1. The calling party sends a session request INVITE message to the S-CSCF of the CSI terminal belonging to the IMS domain.

2. The S-CSCF routes the session request to the CSI IW (CSI Interworking, CSI Interworking Function Entity).

 3. CSI IW performs business logic processing.

 4. The CSI IW initiates a session request to the Tel URI of the CSI terminal to the MGCF (Media Gateway Control Function).

 5. The MGCF initiates a CS call request message to the CS domain of the CSI terminal. After receiving the request message, the CSI terminal identifies the CS MSISDN number of the peer end as the session identifier of the session from the signaling of the CS domain.

 6. The CSI terminal sends a CS call response message to the MGCF.

 7. The MGCF sends a 200 OK response message to the CSI IW.

 8. CSI IW sends 200 0 to 8-〇8〇? .

 9. The S-CSCF forwards 200 OK to the calling side.

 10. The CSI terminal initiates a session request to the IMS of the opposite UE. The request carries the MSISDN number information of the peer as the identifier of the original session combined with the IMS session. The CSI terminal carries this information in the User Agent header field of SIP signaling.

 The CSI terminal can also carry this information in other SIP header fields/messages.

 11. When the CSI IW receives the session request, the session is matched according to the received MSISDN number information, and the matching is successful.

 12. The CSI IW merges the session request with the previous session, and initiates a session change request RE-INVITE message to the peer.

 13. The S-CSCF forwards the RE-INVITE message to the peer terminal.

In this flow, if the first session is a CSI terminal caller, the IMS terminal is called, CSI is terminated. The MSISDN number of the peer end can still be identified as the session identifier, and the session identifier is carried when the second session is initiated.

 Method Embodiment 2. The process of session association when an IMS session is first established between a CSI terminal and an IMS terminal. See Figure 6 for the following specific steps:

 1. The calling party sends a session request INVITE message to the S-CSCF of the CSI terminal belonging to the IMS domain.

 2. The S-CSCF routes the session request to the CSI IW.

 3. CSI IW performs business logic processing.

 4. The CSI IW initiates a session request to the IMS domain of the CSI terminal.

 5. If the session message carries the CS domain number of the peer end, the CSI terminal can use the CS number as the session identifier.

 If the CSI terminal cannot obtain the CS number of the peer from the signaling message, the information can be obtained from other non-sessional channels. For example, this information can be obtained from locally stored data.

 6. The CSI terminal sends a 200 OK response message. The message carries the CS number information of the peer end, indicating that a subsequent CS call is to be bound to the IMS session.

 7. The CSI terminal sends 200 OK to the peer terminal.

 8. The S-CSCF receives the 200 OK response and forwards it to the peer terminal.

 9. The CSI terminal initiates a CS session request to the peer end, and the called number is the CS domain MSISDN number of the peer end. The request is routed to the MGCF.

 The CSI terminal may also carry the called number information of the opposite end as the session identifier in the UUI information of the CS signaling, and identify the original session combined with the call.

 10. The MGCF sends a SIP INVITE message to the CSI IW, where the SIP message carries the Tel URI information of the CS number of the opposite end.

 11. The CSI IW obtains the MSISDN number according to the peer TelURI information in the SIP message, and performs matching.

 12. If the matching is successful, the CSI IW merges the session with the original session and sends a RE-INVITE to the peer terminal.

13. The S-CSCF receives the RE-INVITE response and forwards it to the peer terminal. Method Embodiment 3: The CSI terminal CS calls, and the IMS calling party establishes a session with the peer end. Referring to Figure 7, the following specific steps are included:

 1. The CSI terminal initiates an INVITE session request to the peer, and the request is routed to the CSI IW. When the CSI terminal initiates the request, it carries the session identification information and carries it to the network side in the SIP message.

 The CSI terminal can carry the session identifier in the User Agent header field of the SIP message.

 2. The CSI IW initiates an INVITE request to the peer.

 3. The CSI terminal initiates a CS call request to the peer, and the request is routed to the MGCF.

 The CSI terminal carries the session identification information in the message.

 The CSI terminal can directly use the called number in the CS signaling as an implicit session identifier, and can also carry explicit session identification information in the UUI information.

 4. The MGCF initiates an INVITE request, where the request carries implicit or explicit session identification information mapped in the CS message. The request is routed to the CSI IW.

 5. After receiving the session request, the CSI IW matches according to the session identifier carried in the session.

6. After the matching is successful, the CSI IW merges the second session with the previous session and sends a RE-INVITE request to the peer.

 Corresponding to the above method, the embodiment of the present invention further provides a CSI terminal, which is shown in FIG. 8, which includes an identifier generating unit and a transmitting unit connected to each other; and further includes an information acquiring unit connected to the identifier generating unit.

 The identifier generating unit is configured to generate an identifier corresponding to the first session when the CSI terminal processes the first session.

 The transmitting unit, configured to carry the identifier generated by the identifier generating unit in the message sent when the first session is processed, and the message of the second session associated with the first session, to transmit the identifier to the network side.

The information obtaining unit is configured to obtain the CS domain MSISDN number of the peer end from the first session related message, or obtain the CS domain MSISDN number of the opposite end by using other methods, such as locally stored data, and provide the identifier to the identifier generating unit. It can also be used to obtain the PMI letter of this CSI terminal. Interest.

 Corresponding to the above method, the embodiment of the present invention further provides a CSI interworking function entity, as shown in FIG. 9, which includes an identification unit and a matching unit connected to each other, an identifier holding unit respectively connected to the identification unit and the matching unit, and The associated unit to which the matching unit is connected.

 The identifying unit is configured to identify an identifier carried in a message sent by the CSI terminal.

 The matching unit is configured to match the identifier identified by the identification unit with the identifier saved by the identifier holding unit, and if the matching fails, determine that the received message belongs to the first session, and issue a related indication to the identifier holding unit; If the matching is successful, it is determined that the received message belongs to the second session associated with the first session, and the relevant indication is sent to the associated unit.

 The identifier holding unit is configured to save the identifier identified by the identification unit according to the indication of the matching unit, and record the correspondence between the identifier and the first session.

 The association unit is configured to associate the first session with the second session according to an indication of the matching unit.

 Corresponding to the above method and apparatus, the embodiment of the present invention further provides a system for associating a session, as shown in FIG. 10, including a CSI terminal and a CSI interworking function entity that are connected to each other.

 The CSI terminal is configured to generate an identifier corresponding to the first session when processing the first session, and send a message when processing the first session, and a message of the second session associated with the first session that is subsequently initiated. Carry the logo in it.

 The CSI interworking function entity is configured to: after receiving the message sent by the CSI terminal, identify the identifier carried in the message, and match the locally saved identifier, if the matching fails, determine that the received message belongs to The first session, the identifier carried in the message is saved, and the correspondence between the identifier and the first session is recorded; if the matching is successful, it is determined that the received message belongs to the second session, and the first session is A session is associated with a second session.

 In order to be able to communicate the associated session information, an embodiment of the present invention provides a method for transmitting associated session information, including the following steps:

The CSI terminal or the CSI interworking function entity carries the associated session information in the message interacting with the peer end; and after the peer end receives the message, the associated session information is identified and saved from the message. Further, the associated session includes: a first session and a second session, where the first session is a CS session, and the second session is an IMS session; or the first session is an IMS session, and the second session is a CS session;

 In the CS session in the associated session, the CSI terminal or the CSI interworking function entity carries the associated session information in the UUI information of the CS message that interacts with the peer end; and after receiving the CS message, the peer end is in the UUI information of the message. Identify and save the associated session information.

 In the IMS session in the associated session, the CSI terminal or the CSI interworking function entity carries the associated session information in the existing header field or the newly added header field of the IMS message that interacts with the peer end; and after the peer end receives the IMS message, The associated session information is identified and saved from the header field of the IMS message. For example, the IMS message is an IMS request message, and the associated session information is carried in the user agent header field or carried in the P-Asserted-Identity header field; the IMS message is an IMS response message, and the association is The session information is carried in the server header field; or carried in the P-Asserted-Identity header field.

 In summary, in the method, device, and system for associating a session in the embodiment of the present invention, the CSI terminal generates an identifier corresponding to the first session when processing the first session, and sends a message in the first session, and subsequent The message sent by the second session that is associated with the first session carries the identifier. After receiving the message sent by the CSI terminal, the CSI interworking function entity identifies the identifier carried in the message and matches the locally saved identifier. If the matching fails, determining that the received message belongs to the first session, saving the identifier carried in the message, and recording the correspondence between the identifier and the first session; if the matching is successful, determining that the received message belongs to In the second session, and associating the first session with a second session. Thereby, the CSI terminal and the IMS terminal are interworked.

The method for transmitting the associated session information in the embodiment of the present invention provides a specific delivery manner of the associated session information (identification), that is, the UUI of the CS message that is exchanged between the CSI terminal and the CSI interworking function entity in the CS session (User to The user information carries the associated session information. In the IMS session, the associated session information is carried in the header field of the IMS message exchanged between the CSI terminal and the CSI interworking function entity. The spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and the modifications of the invention

Claims

Rights request  A method for associating a session, comprising the steps of:  The CSI terminal generates an identifier corresponding to the first session when processing the first session, and carries the identifier in a message sent when the first session is processed, and in a message of the second session that is subsequently initiated to be associated with the first session;  After receiving the message sent by the CSI terminal, the CSI interworking function entity identifies the identifier carried in the message and matches the locally saved identifier. If the matching fails, it determines that the received message belongs to the first session. And storing the identifier carried in the message, and recording the correspondence between the identifier and the first session; if the matching succeeds, determining that the received message belongs to the second session, and the first session and the second session Association.  2. The method according to claim 1, wherein the CSI terminal generates the identifier, including one of the following:  The CSI terminal obtains the CS domain MSISDN number of the peer end, and uses the MSISDN number as the identifier;  The CSI terminal uses the PMI information of the local end as the identifier.  The CSI terminal uses the random number corresponding to the first session as the identifier;  The CSI terminal obtains the CS domain MSISDN number of the opposite end, and combines the MSISDN number with the random number as the identifier;  The CSI terminal combines the PMI information of the local end with the random number as the identifier.  The method of claim 2, wherein the CSI terminal obtains the CS domain MSISDN number of the opposite end from the first session related message, or obtains the CS domain MSISDN number of the opposite end by using the locally stored data.  The method according to any one of claims 1 to 3, wherein the CSI terminal transmits the identifier to the network side by one of the following modes: In the CS session, the identifier is carried in the UUI information of the CS message sent to the network side; in the IMS session, the identifier is carried in the header field of the IMS message sent to the network side. The method according to claim 4, wherein the IMS message is an IMS request message, and the identifier is carried in a User Agent header field; or is carried in a P-Asserted-Identity header field;  The IMS message is an IMS response message, and the identifier is carried in the Server header field; or carried in the P-Asserted-Identity header field.  6. A CSI terminal, comprising:  An identifier generating unit, configured to generate an identifier corresponding to the first session when the CSI terminal processes the first session;  The delivery unit is configured to carry the identifier generated by the identifier generating unit in the message sent when the first session is processed, and in the message of the second session associated with the first session, to transmit the identifier to the network side.  The CSI terminal according to claim 6, further comprising:  The information obtaining unit is configured to obtain the CS domain MSISDN number of the peer end from the first session related message, or obtain the CS domain MSISDN number of the peer end by using the locally stored data, and provide the identifier to the identifier generating unit.  8. A CSI interworking function entity, comprising:  An identifying unit, configured to identify an identifier carried in a message sent by the CSI terminal;  a matching unit, configured to match the identifier identified by the identification unit with the identifier saved by the identifier holding unit, and if the matching fails, determine that the received message belongs to the first session, and issue a relevant indication to the identifier holding unit; And determining that the received message belongs to the second session associated with the first session, and issuing a related indication to the associated unit;  An identifier holding unit, configured to save an identifier recognized by the identification unit according to the indication of the matching unit, and record a correspondence between the identifier and the first session;  And an associating unit, configured to associate the first session with the second session according to the indication of the matching unit. 9. A system for associating conversations, comprising: a CSI terminal, configured to generate an identifier corresponding to the first session when processing the first session, and send a message sent when the first session is processed, and a second session that is subsequently initiated to be associated with the first session The message carries the identifier;  The CSI interworking function entity is configured to: after receiving the message sent by the CSI terminal, identify the identifier carried in the message, and match the locally saved identifier, if the matching fails, determine that the received message belongs to the a first session, storing an identifier carried in the message, and recording a correspondence between the identifier and the first session; if the matching is successful, determining that the received message belongs to the second session, and the first session is Associated with the second session.  10. A method for communicating associated session information, comprising the steps of:  The CSI terminal or the CSI interworking function entity carries the associated session information in the message interacting with the peer end;  After receiving the message, the peer identifies and saves the associated session information from the message.  The method of claim 10, wherein, in the CS session in the associated session, the CSI terminal or the CSI interworking function entity carries the associated session information in the UUI information of the CS message that interacts with the peer end; And after the peer receives the CS message, the associated session information is identified and saved from the UUI information of the message.  The method of claim 10, wherein, in the IMS session in the associated session, the CSI terminal or the CSI interworking function entity carries the associated session information in a header field of the IMS message that interacts with the peer end; And after the peer receives the IMS message, the associated session information is identified and saved from the header field of the IMS message.  The method of claim 12, wherein the IMS message is an IMS request message, and the associated session information is carried in a User Agent header field; or carried in a P-Asserted-Identity header field;  The IMS message is an IMS response message, and the associated session information is carried in the Server header field; or carried in the P-Asserted-Identity header field.