CN107547819B

CN107547819B - Video switching method, device and system

Info

Publication number: CN107547819B
Application number: CN201610505753.7A
Authority: CN
Inventors: 刘竞翔
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2016-06-29
Filing date: 2016-06-29
Publication date: 2020-04-28
Anticipated expiration: 2036-06-29
Also published as: CN107547819A

Abstract

The invention provides a video switching method, which comprises the following steps: a Mobile Switching Center (MSC) server sends a first dialogue establishing message to a service centralization and continuous application server (SCC AS), wherein the first dialogue establishing message carries first information; the MSC server receives a response message, wherein the response message carries the first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; and the MSC server sends a second dialogue establishing message to a Video Interworking Gateway (VIG) to establish the second dialogue, so that the VIG forwards the second dialogue establishing message to the SCC AS and establishes media connection. By adopting the scheme, on one hand, the conversion of the video media between the circuit domain format and the IMS format can be realized by using VIG in the video switching process; on the other hand, the information interaction required by the switching and the calling can be completed through the SIP signaling, so that the switching and the calling can be normally carried out.

Description

Video switching method, device and system

Technical Field

The present invention relates to the field of communications, and in particular, to a method, an apparatus, and a system for video switching.

Background

Video telephony is a service provided by an IMS (IP Multimedia Subsystem) network, and both parties to the telephony can interact with graphics and voice by transmitting video and voice signals simultaneously in a media stream. The IMS uses SIP (Session Initiation Protocol) as a control signaling, has the characteristics of separate bearer control and irrelevant access, and has the capability of providing a unified multimedia service for users in different networks, which is an evolution direction of the current telecommunication network. Under the 3GPP system, a user performing an IMS video call generally accesses from an LTE (Long term evolution) network. When the user moves to a CS (Circuit switched) network only, the CS network needs to be switched from LTE.

Fig. 1 is a network configuration diagram for performing the handover: UE a is a UE (User Equipment) that is handed over. The MSC Server (Mobile Switch Center Server) is a switching Server to which the UE a belongs after being handed over to the circuit domain. The server provides handover services for UE a and provides call control functions after handover. MME (Mobility Management Entity) is a Management network element of UE a in the packet switched domain. Before handover, UEA resides under MME and connects to S-CSCF (Serving Call session control Function) through IP connection provided by MME. When needing to switch to the circuit domain, the MME sends a switching request to the MSC, and interacts with the MSC to complete the switching process. The S-CSCF is the S-CSCF providing services for UE a. SCC AS (service centralization and Continuity Application Server) is an AS that provides call Continuity services in an IMS network. In the switching process, the SCC AS is responsible for implementing communication between the switched cs session leg and the call remote end. The SCC AS may be co-located with a supplementary service AS providing service logic for the UE, or may be separately located. The interface between the MSC Server and the SCC AS is an IP-based SIP interface. UE B is the far end of the dialog with UE a. The MGW is a media gateway under the MSC Server. After switching, media connection is established between the UE A and the MGW, meanwhile, media connection is also established between the MGW and the remote UE B, and the UE A and the UE B carry out communication through the MGW.

Fig. 2 is a flow of the video call making this handover. This process is called vSRVCC (Single Radio Video Call Continuity). In this handover procedure, SIP signaling is typically employed between the MSC Server and the IMS. Through SIP signaling, MSC Server can carry out Options inquiry process, and obtain the current switching dialogue type from SCC AS; the SCC AS can send the current call state to the MSC Server; carrying out call related service of IMS domain; in the aspect of the media plane, the media stream between the UE a and the MGW after the handover is transmitted according to the h.324m specification, and the voice and the image are multiplexed in one media stream by using the h.223 specification. Between MGW and IMS, voice and image are in two media streams separately, and the coding of image and coding of voice are determined by the negotiation between MSC Server and UE B. Because the two parties transmit different streams, the MGW needs to convert the media stream, which is called as a Video Interworking Gateway (VIG) function.

As can be seen from the analysis of the vSRVCC handover procedure, the MGW must support the VIG function to perform vSRVCC. However, in some networks, MGWs often do not have VIG capability, and a separate network element from a third party vendor needs to be introduced to provide VIG services. The network structure is shown in fig. 3. The VIG is an MSC Server and an interworking network element between the MGW and the IMS network. Between VIG and MSC Server, signaling interface of circuit domain such as BICC/ISUP is generally adopted. And MGW, the media transmission specification of H.324M is followed. Meanwhile, between VIG and IMS network, the signaling plane adopts SIP transmission specification, and the media plane adopts RTP transmission specification. The VIG functions as a signaling and media switch between these.

In a network using VIG, the procedure of vSRVCC handover is shown in fig. 4, and includes:

s401, UE A calls UE B to carry out video call, and a switching decision is carried out between UE A and MME to decide to switch to a circuit

A switching network.

And S402, the MME sends a switching request of the video service to the MSC Server and requires to switch.

And S403. the MSC Server sends an Add command to the MGW to request to establish a video media termination point at the wireless side.

S404.MGW applies for media resource, returns T1 terminal point to establish successfully.

And S405, the MSC Server performs switching preparation work on the wireless side and applies for resources required by the video media.

S406, the MSC Server sends an Add command to the MGW to request to establish a video media termination point of the VIG.

And S407, the MGW applies for the media resource and returns to the T2 termination point of the media connection between the VIGs to establish successfully.

S408, MSC Server sends BICC (Bearer Independent Call Control Protocol), which bears Independent Call Control

protocol)/IAM (Initial address message for ISUP (ISDN User Part) signaling,

initial address message) to the VIG, carrying media information for the video.

And S409, carrying out interactive processing by the VIG, and sending the INVITE of the video service to the SCC AS.

The SCC AS receives the INVITE, converts the INVITE into an Update and sends the Update to the UE B. Informing UE B to update the media.

S4010. the msc Server also sends a handover response to the MME after sending the IAM message.

S4011.mme sends handover command to UE a. The UEA starts migrating towards the circuit switched network.

S4012, UE B receiving the Update message returns 200OK which is processed successfully.

S4013.scc returns 200OK to VIG.

And S4014, converting VIG into ANM and sending the ANM to the MSC Server.

And S4015, the wireless switching on the MSC Server is completed, and the UE A completes the access in the MSC Server.

And S4016, the MSC Server sends a switching completion message to the MME.

Above scheme, because the communication between MSC Server and SCC AS forwards through VIG, and MSC Server and VIG have adopted circuit domain signaling interfaces such AS BICC/ISUP, consequently vSRVCC switches can have following problem:

the MSC Server and SCC AS can not determine whether the media type is video or voice by the Options message of SIP. In the switching process, the INFO message sent by the SCC AS cannot be transmitted to the MSC Server, and the MSC Server cannot know the state of the session. After the switching is completed, the supplementary service related to the call can not be carried out without using SIP signaling. That is, although the VIG implements media conversion, since an interface with the MSC Server is BICC or ISUP signaling, the processing capability of the handover is limited.

Aiming at the problem that the switching processing capability is limited when video switching is carried out through independent network element VIG forwarding in the related technology, no effective solution is provided at present.

Disclosure of Invention

The invention provides a video switching method, a device and a system, which at least solve the problem that in the process of carrying out video switching by independent network element VIG forwarding, as the interfaces of VIG and MSC Server are BICC or ISUP signaling, the processing capacity of switching is limited.

According to an aspect of the present invention, there is provided a video switching method, including:

a Mobile Switching Center (MSC) server sends a first dialogue establishing message to a service centralization and continuous application server (SCC AS), wherein the first dialogue establishing message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; the MSC server receives a response message of the SCC AS, wherein the response message carries the first information; and the MSC server sends a second dialogue establishing message to a Video Interworking Gateway (VIG) to establish the second dialogue, so that the VIG forwards the second dialogue establishing message to the SCCAS and establishes media connection. Wherein the second session setup message includes second information for associating with the first session. The second information for associating the first dialog includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

The video switching method also comprises that after the video switching is completed, the MSC server receives an Update or Re-Invite request message sent by the user equipment of the calling opposite terminal, updates the media of the wireless side and responds to the request.

According to an aspect of the present invention, there is also provided a video switching method, including: a service centralization and continuous application server SCC AS receives a first dialogue establishing message sent by a mobile switching center MSC server, wherein the first dialogue establishing message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; the SCC AS sends a response message to the MSC server, wherein the response message carries the first information; and after the second session is established, the SCC AS receives a second session establishment message forwarded by a Video Interworking Gateway (VIG) and establishes the media connection. Wherein the second session setup message includes second information for associating with the first session; the SCC AS receiving a second session establishment message sent by a video interworking gateway, VIG, and establishing the media connection includes: and the SCC AS associates the first conversation with the second conversation through the second information and informs the called user equipment of updating media. The second information for associating the first dialog includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

After the switching is completed, the SCC AS receives an Update or Re-Invite message sent by a user equipment at a calling opposite end, and sends the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and the called user equipment; and sending an Update or Re-Invite message to the MSC server to enable the MSC server to Update media on a wireless side.

According to an aspect of the present invention, there is also provided a video switching apparatus, including: a first sending module, configured to send a first session establishment message to a service centralization and continuity application server SCC AS, where the first session establishment message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; a first receiving module, configured to receive a response message, where the response message carries the first information; and the second sending module is used for sending a second session establishment message to a Video Interworking Gateway (VIG) and establishing the second session so that the VIG forwards the second session establishment message to the SCC AS and establishes media connection.

Wherein the second session setup message includes second information for associating with the first session. The second information for associating the first dialog includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

The video switching device further comprises a second receiving module, configured to receive an Update or Re-Invite request message after video switching is completed, Update media on the wireless side, and respond to the request.

According to an aspect of the present invention, there is also provided a video switching apparatus, including: a third receiving module, configured to receive a first session establishment message sent by a mobile switching center MSC server, where the first session establishment message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; a third sending module, configured to send a response message to the MSC server, where the response message carries the first information; and the fourth receiving module is used for receiving a second dialogue establishing message forwarded by a Video Interworking Gateway (VIG) after the second dialogue is established, and establishing the media connection.

Wherein the second session setup message includes second information for associating with the first session; the fourth receiving module is further configured to: and associating the first dialog with the second dialog through the second information, and informing the called user equipment of updating media. The second information for associating the first dialog includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

The video switching apparatus further includes a fourth sending module, configured to receive an Update or Re-Invite message sent by a called user equipment after switching is completed, and send the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and the called user equipment; and sending an Update or Re-Invite message to the MSC server to enable the MSC server to Update media on a wireless side.

According to an aspect of the present invention, there is also provided a video switching system, including: the method comprises the following steps that a Mobile Switching Center (MSC) server, a service centralization and continuous application server (SCC AS) and a Video Interworking Gateway (VIG) are adopted, wherein the MSC server sends a first dialogue establishing message to the SCCAS, and the first dialogue establishing message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session; the SCC AS responds to the first dialogue establishing message, and the first dialogue establishing message carries first information; the MSC server sends a second dialogue establishing message to a Video Interworking Gateway (VIG) to establish the second dialogue; the VIG forwards the second session establishment message to the SCC AS; and the SCC AS receives a second dialogue establishing message forwarded by a Video Interworking Gateway (VIG) and establishes the media connection.

Wherein the second session setup message includes second information for associating with the first session; the SCC AS receiving a second session establishment message sent by a video interworking gateway, VIG, and establishing the media connection includes: and the SCC AS associates the first conversation with the second conversation through the second information and informs the called user equipment of updating media. The second information for associating the first dialog includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

The video switching system further comprises that after the switching is completed, the SCC AS receives an Update or Re-Invite message sent by a called user and sends the Update or Re-Invite message to the VIG, and the VIG modifies media between the VIG and the called user equipment; and sending an Update or Re-Invite message to the MSC server, and the MSC server updating media at a wireless side.

By adopting the invention, when vSRVCC is switched, MSC Server respectively establishes BICC or ISUP dialogue passing through VIG and SIP dialogue to SCC AS, so that vSRVCC process can utilize VIG to realize conversion of video media between circuit domain format and IMS format. On the other hand, the information interaction required by the switching and the calling can be completed through the SIP signaling, so that the switching and the calling can be normally carried out.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a network structure diagram of vSRVCC handover according to the related art;

fig. 2 is a flow chart of a vSRVCC handover for a related video call;

fig. 3 is a network structure diagram related to vSRVCC handover using VIG;

fig. 4 is a flow chart of vSRVCC handover in a network using VIG;

fig. 5 is a flowchart of a video switching method according to a first embodiment of the present invention;

fig. 6 is a flowchart of a video switching method according to a second embodiment of the present invention;

fig. 7 is a block diagram of a video switching system according to a third embodiment of the present invention;

fig. 8 is a flow diagram of a vSRVCC handover in a steady state dialog according to an embodiment of the present invention;

fig. 9 is a flow of vSRVCC handover during a ring-state dialog according to an embodiment of the present invention;

fig. 10 is a flowchart illustrating a process of receiving an Update message by the SCC AS after handover according to an embodiment of the present invention;

FIG. 11 is a block diagram of a video switching apparatus according to an embodiment of the present invention;

fig. 12 is a block diagram of a video switching apparatus according to an embodiment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings. It should be particularly noted that the references to "first" and "second" in the following text do not limit the embodiments of the present invention, but are used merely for convenience of distinction.

An embodiment of the present invention provides a video switching method, and fig. 5 is a video switching method according to an embodiment of the present invention, as shown in fig. 5, including the following steps:

s501, the MSC server sends a first dialogue establishing message to the SCC AS, wherein the first dialogue establishing message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session;

s502, the MSC server receives a response message, and the response message carries the first information;

s503, the MSC server sends a second dialogue establishing message to the VIG, and establishes the second dialogue, so that the VIG forwards the second dialogue establishing message to the SCC AS and establishes media connection.

Preferably, the second session setup message includes the first session identification.

Preferably, the first session identification comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

Preferably, the above video handover method further includes, after the video handover is completed, the MSC server receiving an Update or Re-Invite request message, updating media on the wireless side, and responding to the request.

An embodiment of the present invention provides a video switching method, and fig. 6 is a video switching method according to an embodiment of the present invention, as shown in fig. 6, including the following steps:

s601.SCC AS receives a first dialogue establishing message sent by a mobile switching center MSC server, wherein the first dialogue establishing message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session;

s602, the SCC AS sends a response message to the MSC server, wherein the response message carries the first information;

and S603, after the second session is established, the SCC AS receives a second session establishment message forwarded by a Video Interworking Gateway (VIG) and establishes the media connection.

Preferably, the second session setup message includes a first session identifier;

preferably, the SCC AS receives a second session establishment message sent by a video interworking gateway VIG, and establishing the media connection includes: and the SCC AS associates the first conversation with the second conversation through the first conversation identification and informs the called user equipment of updating media.

The first session identification comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

Preferably, the above video switching method further includes, after the switching is completed, the SCC AS receiving an Update or Re-Invite message sent by the called user equipment, and sending the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and the called user equipment; and sending an Update or Re-Invite message to the MSC server so that the MSC server updates the media of the wireless side.

An embodiment of the present invention provides a video switching system, and fig. 7 is a video switching system according to an embodiment of the present invention, as shown in fig. 7, including: a mobile switching center MSC server 701, a service centralization and continuity application server SCC AS702 and a video interworking gateway VIG 703,

the MSC server 701 sends a first session establishment message to the SCC AS702, where the first session establishment message carries first information; wherein the first information is used to inform the SCC AS702 that the first session does not establish a media connection and that a media connection is established by a second session;

the SCC AS702 responds to the first session establishment message, which carries first information; the MSC server 701 sends a second session establishment message to the video interworking gateway VIG 703, and establishes the second session;

the VIG 703 forwarding the second session establishment message to the SCC AS 702;

the SCC AS702 receives the second session establishment message forwarded by the video interworking gateway VIG 703, and establishes the media connection.

the SCC AS702 receives a second session establishment message sent by the video interworking gateway VIG 703, and establishing the media connection includes: the SCC AS702 associates the first dialog and the second dialog with the first dialog identifier and notifies the called user equipment to update the media.

Preferably, the video switching system further includes that, after the switching is completed, the SCC AS702 receives an Update or Re-Invite message sent by the called user, and sends the Update or Re-Invite message to the VIG 703, where the VIG 703 modifies media between the VIG and the called user equipment; an Update or Re-Invite message is sent to the MSC server 701, and the MSC server 701 updates the media on the wireless side.

According to the above embodiments, when vSRVCC is switched, the MSC Server respectively establishes a BICC or ISUP session through the VIG and an SIP session to the SCC AS, so that the vSRVCC process can utilize the VIG to implement the conversion of the video media between the circuit domain format and the IMS format. On the other hand, the information interaction required by the switching and the calling can be completed through the SIP signaling, so that the switching and the calling can be normally carried out.

In order to make the technical solution and implementation method of the present invention clearer, the following describes the implementation process in detail with reference to the preferred embodiments.

As shown in fig. 8, the procedure for performing vSRVCC handover in a steady-state video session according to the embodiment of the present invention includes:

and S801. the UE A calls the UE B to carry out video call, and the UE A and the MME carry out switching decision to decide to switch to a circuit switching network.

And S802.MME sends a switching request of video service to MSC Server to require switching.

And S803, because an SIP interface exists between the MSC Server and the SCC AS, sending an Options message to the SCC AS and inquiring about the service type of the switching.

And S804, the SCC AS judges that the current conversation is a video conversation, returns a 200OK message and informs the MSC Server that the switched service type is a video service.

And S805, the MSC Server sends an Add command to the MGW to request to establish a video media termination point at the wireless side.

S806.MGW applies for media resource, returns T1 terminal point to establish successfully.

And S807. the MSC Server performs switching preparation work on the wireless side and applies for resources required by the video media.

And S808, the MSC Server sends the INVITE message through the SIP interface. The session description protocol SDP request in the INVITE message carries a media message that informs the SCC AS not to establish a media connection for the session, and also tells the SCC AS that the media is to be established subsequently by another session.

S809, the SCC AS that received the INVITE message returns 200OK because the current dialog is a steady state dialog. And also contains a media message that the media connection is not established in the SDP answer of the 200 OK.

S8010. the MSC Server receives the 200OK and obtains the full reference for the session, including the CallId, From Tag and To Tag. Because of the nature of the media information, the MSC Server and the SCC AS do not perform media establishment, but wait for a subsequent session to establish media. Then MSC Server sends Add command to MGW to request to establish video media terminal point of VIG.

S8011.MGW applies for media resource, returns T2 end point to build successfully.

S8012, MSC Server sends IAM message of BICC/ISUP signaling to VIG, carrying media information of video. And simultaneously carries the reference information of the first dialogue, including CallId, From Tag and To Tag.

And S8013, the VIG performs interactive processing and sends the INVITE of the video service to the SCC AS. The reference information of the first dialog described above is also forwarded to the SCC AS.

And S8014, the SCC AS receives the INVITE and knows the association relation between the session and the first session by referring to the information. Since the session establishes media, an Update message is sent to UE B. Informing UE B to update the media.

S8015. the msc Server also sends a handover acknowledgement to the MME after sending the IAM.

S8016.mme sends handover command to UE a. UE A starts to migrate to the circuit domain network.

S8017, UE B receiving Update message returns 200OK for successful process.

S8018.scc returns 200OK to VIG.

S8019.vig converts to ANM (Answer Message) and sends it to MSC Server.

And S8020, completing the wireless switching on the MSC Server, and completing the access of the UE A in the MSC Server.

And S8021, the MSC Server sends a switching completion message to the MME.

As shown in fig. 9, the procedure of performing vSRVCC handover in a ringing video session according to the embodiment of the present invention is as follows:

and S901, the UE A calls the UE B to carry out video call, and a switching decision is carried out between the UE A and the MME to decide to switch to a circuit switching network.

And S902, the MME sends a switching request of the video service to the MSC Server and requires to switch.

S903, because there is SIP interface between MSC Server and SCC AS, sends Options message to SCC AS to inquire the service type of this switching.

And S904. the SCC AS judges that the current conversation is a video conversation, returns a 200OK message and informs the MSC Server that the switched service type is a video service.

S905.MSC Server sends Add command to MGW to request to establish video media terminal point at wireless side.

And S906. the MGW applies for the media resource and returns T1 to establish the termination successfully.

And S907. the MSC Server performs switching preparation work on the wireless side and applies for resources required by the video media.

And S908, the MSC Server sends the INVITE message through the SIP interface. The SDP request in the INVITE message carries a media message that informs the SCC AS not to establish a media connection for the session. And also contains an identifier that tells the other party that the media is subsequently established by another session.

S909. SCC AS receiving INVITE message, return to 183, because the current dialog is a ringing state dialog. And also contains a media message in the SDP answer at 183 that the media connection is not established. The MSC Server receives 183 and obtains the full reference for the session, including the CallId, From Tag, and To Tag. Because of the nature of the media information, MSCServer and SCC AS do not perform media establishment, but wait for a subsequent session to establish media. The MSC Server returns PR ACK to 183, and the SCC AS returns 200OK message of PR ACK.

S9010.SCC AS sends INFO message to MSC Server, wherein the state carrying the switching dialog is ringing state. The MSC Server returns a 200OK message of the response.

S9011, MSC Server sends Add command to MGW to request to establish video media termination point of VIG.

And S9012, applying for the media resource by the MGW, and returning to T2 to establish the termination successfully.

S9013, MSC Server sends IAM message of BICC/ISUP signaling to VIG, carrying media information of video.

And simultaneously carries the reference information of the first dialogue, including CallId, From Tag and To Tag.

And S9014, performing interactive processing by the VIG, and sending the INVITE of the video service to the SCC AS. The reference information of the first dialog described above is also forwarded to the SCC AS.

And S9015. the SCC AS receives the INVITE and knows the association relationship between the second conversation and the first conversation by referring to the information.

Since the session establishes a medium, Update is transmitted to UE B. Informing UE B to update the media.

S9016. the msc Server also sends a handover response to the MME after sending the IAM.

S9017. the mme sends a handover command to UE a. UE A starts to migrate to the circuit domain network.

S9018, the UE B which receives the Update message returns 200OK which is processed successfully.

S9019.scc returns 200OK to VIG.

And S9020, converting the VIG into ANM and sending the ANM to the MSC Server.

And S9021, completing wireless switching on the MSC Server, and completing access of the UE A in the MSC Server.

S9022, the MSC Server sends a switching completion message to the MME.

S9023, the called UE B goes off hook later, and sends a 200OK message to the SCC AS. The SCC AS returns an ACK message.

S9024, the SCC AS receiving the 200OK also sends the 200OK to the MSC Server. The MSC Server returns an ACK message.

S9025, MSC Server sends CONNECT message to UE A to inform calling user to carry out conversation.

AS shown in fig. 10, the SCC AS after switching receives the Update or Re-Invite message AS follows:

s1001.UE B sends Update or Re-Invite message to SCC AS.

S1002, the SCC AS judges that two dialogs are related to the dialog in which the Update or the Re-Invite occurs currently, and forwards the Update or the Re-Invite to the VIG first.

S1003.VIG updates media according to the content of Update or Re-Invite

S1004.VIG returns 200OK, carrying response to update media

S1005.SCC AS sends Update or Re-Invite to MSC Server of another associated dialog.

And S1006. the MSC Server updates the media of the wireless side.

And S1007, the MSC Server returns 200 OK.

And S1008, the SCC AS returns 200OK to the UE B.

It should be noted that the steps illustrated in the flowcharts of the figures may be performed in a computer system such as a set of computer-executable instructions and that, although a logical order is illustrated in the flowcharts, in some cases, the steps illustrated or described may be performed in an order different than presented herein.

The embodiment of the invention also provides a video switching device which can be used for realizing the method. Fig. 11 is a video switching apparatus according to an embodiment of the present invention, as shown in fig. 11, including: a first sending module 1101, configured to send a first session establishment message to a service centralization and continuity application server SCC AS, where the first session establishment message carries first information;

a first receiving module 1102, configured to receive a response message, where the response message carries the first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session;

a second sending module 1103, configured to send a second session establishment message to a video interworking gateway VIG, and establish the second session, so that the VIG forwards the second session establishment message to the SCC AS and establishes a media connection.

The device is applied to the MSC Server.

Preferably, the apparatus further includes a second receiving module, configured to receive an Update or Re-Invite request message after the video handover is completed, Update media on the wireless side, and respond to the request.

An embodiment of the present invention further provides another video switching apparatus, as shown in fig. 12, including: a third receiving module 1201, configured to receive a first session setup message sent by a mobile switching center MSC server, where the first session setup message carries first information;

a third sending module 1202, configured to send a response message to the MSC server, where the response message carries the first information; wherein the first information is used to inform the SCC AS that the first session does not establish a media connection and that a media connection is established by a second session;

a fourth receiving module 1203, configured to receive the second session establishment message forwarded by the video interworking gateway VIG after the second session is established, and establish the media connection.

The above described apparatus is applied to the SCC AS.

preferably, the fourth receiving module 1203 is further configured to: and associating the first conversation with the second conversation through the first conversation identification, and informing the called user equipment of updating media.

Preferably, the apparatus further includes a fourth sending module, configured to receive an Update or Re-Invite message sent by the called user equipment after the handover is completed, and send the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and the called user equipment; and sending an Update or Re-Invite message to the MSC server so that the MSC server updates the media of the wireless side.

It should be noted that the video switching apparatus described in the apparatus embodiment corresponds to the above-mentioned method embodiment, and the specific implementation process thereof has been described in detail in the method embodiment, and is not described herein again.

To sum up, according to the above embodiments of the present invention, when vSRVCC is switched, the MSC Server respectively establishes a BICC or ISUP session through the VIG and an SIP session to the SCC AS, so that, on one hand, the vSRVCC process can use the VIG to implement the conversion of the video media between the circuit domain format and the IMS format. On the other hand, the information interaction required by the switching and the calling can be completed through the SIP signaling, so that the switching and the calling can be normally carried out.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed over a network of multiple computing devices, and they may alternatively be implemented by program code executable by a computing device, such that they may be stored in a storage medium and executed by a computing device, or they may be separately fabricated into various integrated circuit modules, or multiple modules or steps thereof may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A video switching method, comprising:

a Mobile Switching Center (MSC) server sends a first dialogue establishing message to a service centralization and continuous application server (SCC AS), wherein the first dialogue establishing message carries first information; wherein the first information is used for notifying the SCC AS that the first session does not establish media connection and a second session establishes media connection;

the MSC server receives a response message of the SCC AS, wherein the response message carries the first information;

and the MSC server sends a second dialogue establishing message to a Video Interworking Gateway (VIG) to establish the second dialogue, so that the VIG forwards the second dialogue establishing message to the SCC AS and establishes media connection.

2. The video switching method of claim 1, wherein the second session setup message includes second information for associating with the first session.

3. The video switching method of claim 2, wherein the second information for associating with the first session comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

4. The video handover method according to claim 1, further comprising, after the video handover is completed, the MSC server receiving an Update or Re-Invite request message sent by a calling peer ue, updating media on a wireless side, and responding to the Update or Re-Invite request.

5. A video switching method, comprising:

a service centralization and continuity application server SCC AS receives a first session establishment message sent by a mobile switching center MSC server, wherein the first session establishment message carries first information, the first information is used for informing the SCC AS that the first session does not establish media connection and a second session establishes media connection;

the SCC AS sends a response message to the MSC server, wherein the response message carries the first information;

and after the second session is established, the SCC AS receives a second session establishment message forwarded by a Video Interworking Gateway (VIG) and establishes the media connection.

6. The video switching method according to claim 5, wherein the second session establishment message includes second information for associating with the first session;

the SCC AS receiving a second session establishment message sent by a video interworking gateway, VIG, and establishing the media connection includes: and the SCC AS associates the first conversation with the second conversation through the second information and informs the called user equipment of updating media.

7. The video switching method of claim 6, wherein the second information for associating with the first session comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

8. The video switching method according to claim 5, further comprising, after the switching is completed, the SCC AS receiving an Update or Re-Invite message sent by a calling peer user equipment, and sending the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and a called user equipment; and sending the Update or Re-Invite message to the MSC server to enable the MSC server to Update media on a wireless side.

9. A video switching apparatus, comprising:

a first sending module, configured to send a first session establishment message to a service centralization and continuity application server SCC AS, where the first session establishment message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish media connection and that a second session establishes media connection;

a first receiving module, configured to receive a response message of the SCC AS, where the response message carries the first information;

and the second sending module is used for sending a second session establishment message to a Video Interworking Gateway (VIG) and establishing the second session so that the VIG forwards the second session establishment message to the SCC AS and establishes media connection.

10. The video switching apparatus according to claim 9, wherein the second session setup message includes second information for associating with the first session.

11. The video switching apparatus according to claim 10, wherein the second information for associating the first session comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

12. The apparatus of claim 9, further comprising a second receiving module, configured to receive an Update or Re-Invite request message sent by a calling peer ue after the video handover is completed, Update media on a wireless side, and respond to the Update or Re-Invite request.

13. A video switching apparatus, comprising:

a third receiving module, configured to receive a first session establishment message sent by a mobile switching center MSC server, where the first session establishment message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish media connection and that a second session establishes media connection;

a third sending module, configured to send a response message to the MSC server, where the response message carries the first information;

and the fourth receiving module is used for receiving a second dialogue establishing message forwarded by a Video Interworking Gateway (VIG) after the second dialogue is established, and establishing the media connection.

14. The video switching apparatus according to claim 13, wherein the second session setup message includes second information for associating with the first session;

the fourth receiving module is further configured to: and associating the first dialog with the second dialog through the second information, and informing the called user equipment of updating media.

15. The video switching apparatus according to claim 14, wherein said second information for associating with the first session comprises at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

16. The video switching apparatus according to claim 13, further comprising a fourth sending module, configured to receive an Update or Re-Invite message sent by a called user equipment after the switching is completed, and send the Update or Re-Invite message to the VIG, so that the VIG modifies media between the VIG and the called user equipment; and sending the Update or Re-Invite message to the MSC server to enable the MSC server to Update media on a wireless side.

17. A video switching system, comprising: a mobile switching center MSC server, a service centralization and continuous application server SCC AS and a video intercommunication gateway VIG,

the MSC server sends a first session establishment message to the SCC AS, wherein the first session establishment message carries first information; wherein the first information is used to inform the SCC AS that the first session does not establish media connection and that a second session establishes media connection;

the SCC AS receives and responds to the first dialogue establishing message, and the first dialogue establishing message carries first information;

the MSC server sends a second dialogue establishing message to a Video Interworking Gateway (VIG) to establish a second dialogue;

the VIG forwards the second session establishment message to the SCC AS;

and the SCC AS receives a second dialogue establishing message forwarded by a Video Interworking Gateway (VIG) and establishes the media connection.

18. The video switching system according to claim 17, wherein said second session setup message includes second information for associating with the first session;

the SCC AS receiving a second session establishment message sent by a video interworking gateway, VIG, and establishing the media connection includes:

and the SCC AS associates the first conversation with the second conversation through the second information and informs the called user equipment of updating media.

19. The video switching system of claim 18, wherein said second information for associating with the first session includes at least one of: a CallId identification of the first session, a From identification of the first session, a To identification of the first session.

20. The video switching system according to claim 17, further comprising, after the switching is completed, the SCCAS receiving an Update or Re-Invite message sent by a calling peer user equipment and sending the Update or Re-Invite message to the VIG, the VIG modifying media between the VIG and a called user equipment; and sending the Update or Re-Invite message to the MSC server, and the MSC server updating media at a wireless side.