KR20040076662A - Interoperation method of video telephony between wcdma network and cdma2000 1xev-do network - Google Patents

Abstract

PURPOSE: A video phone interworking method between a WCDMA(Wideband CDMA) network and a CDMA2000 2XEV_DO network is provided to process an H.245 signaling, and to configure a speech path between an H.323 terminal and an H.324M terminal, thereby enabling a video phone call between the two terminals. CONSTITUTION: An H.323 video terminal(110) registers in a GK(Gatekeeper)(126)(201). The GK(126) transmits a confirm message(202). If a video phone is attempted, an admission request with a gatekeeper-routed call signaling is transmitted(203). An H.225 call signaling setup message is transmitted to the GK(126)(205). The GK(126) transmits the H.225 call signaling setup message to an IMG(Interworking Media Gateway)(130)(206). The IMG(130) transmits a setup signalling message to an SG(Signaling Gateway)(128)(207). The SG(128) executes an IAM signal process(208). A CGS(106) attempts a call connection(209), and delivers an ANM message to the SG(128)(210). The SG(128) processes the setup message(211). A speech path is formed between the IMG(130) and the video terminal(110)(212). The IMG(130) negotiates a level for an error recovery(213), and processes a connect message(214). An H.245 signaling is processed(215), and an end-to-end speech path is configured between the video terminal(110) and an H.324M terminal(100)(216).

Description

Video telephony interworking between WCDMA network and CDM2000 2000 ＸE-DO network {INTEROPERATION METHOD OF VIDEO TELEPHONY BETWEEN WCDMA NETWORK AND CDMA2000 1XEV-DO NETWORK}

The present invention relates to video telephony in a CDMA2000 1X EV-DO and a WCDMA network, and more particularly, to a method of interworking video telephony between a WCDMA network and a CDMA1X EV-DO.

The basic concept of cellular mobile communication was proposed by Bell Labs in the 1940's, and the actual commercial service was rapidly developed in 1983 with the launch of Advanced Mobile Phone Service (AMPS) in the United States. This analog AMPS is called first generation mobile communication.

The Code Division Multiple Access (CDMA) mobile communication system uses a global positioning system (GPS) at the base station, and the North American-oriented synchronous method in which all base stations and terminals operate in time, and the European-oriented asynchronous method that does not use GPS at the base station. There is a way.

Synchronous mobile communication methods are classified into CDMAONE which is 2G (Generation) generation and CDMA2000 which is 3G IMT-2000 series.

Synchronous CDMA that defines IS-2000 as the basis is CDMA2000 1X and CDMA2000 3X. The CDMA2000 1X uses a single 1.25MHz frequency width, just like the existing IS-95, while the CDMA2000 3X uses up to three existing IS-95 frequency widths.

The IMT-2000 enables roaming using the same frequency band (2 GHz) around the world. There are two types of European asynchronous CDMA and North American synchronous CDMA. Asynchronous CDMA is called Wideband CDMA (W-CDMA), and synchronous CDMA is also referred to as MC-CDMA (Multi Carrier CDMA).

1X EV is based on the High Data Rate (HDR) protocol, a high-speed packet data method proposed by Qualcomm.It is 1X EV-DO (Data Only) that transmits only data and 1X EV-DV that transmits voice and data simultaneously. There is a (Data and Voice) method.

In order to provide video telephony in the IMT-2000 network, H.323 or H.324M, an international standard defined by the International Telecommunication Union (ITU), must be implemented in the system. H.323 is a video telephony service in the IP network, a packet data network, and H.324M is an improvement on the existing H.324 for wireless network. H.324 is a system protocol developed based on PSTN network, and H.324M (Mobile) is an improvement of H.324 for mobile communication.

The H.324M video telephony service provided by the WCDMA network was circuit-based, and the H.323 video telephony service provided by the synchronous CDMA2000 1XEV-DO network was packet-based.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem in the related art, and an object thereof is to provide a call processing method capable of video telephony between an H.324M based video terminal and an H.323 based video terminal.

1 is a view showing an embodiment of a system for performing a video telephony interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

2 is a diagram illustrating a video call call processing procedure from an H.323 video terminal to an H.324M video terminal according to an embodiment of a video telephony interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

3 is a diagram illustrating a video call call processing procedure from an H.324M video terminal to an H.323 video terminal in an embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

4 is a diagram illustrating a video call call processing procedure from an H.324M video terminal to an H.323 video terminal in another embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

5 is a diagram illustrating an IMG protocol stack in an embodiment of a video telephony interworking method between a WCDMA network and a CDMA2000 1X EV-DO network in accordance with the present invention.

In order to achieve the above object, the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network according to the first aspect of the present invention is a gatekeeper when an admission request is transmitted from an H.323 video terminal. Sending an H.225 call signal setup message to the IMG; Sending, by the IMG, sigtran signal processing including the called number to the SG; Performing, by the SG, IAM signal processing on the CGS of the mobile circuit; Sending a ANM message to the SG when the CGS attempts to connect to a modem of the H.324M terminal and the H.324M terminal responds; The SG processing the Sigtran message in response to the response of the H.324M terminal to the IMG; A call path is formed between the IMG and the H.324M, and the IMG performs a level negotiation on error recovery between the H.324M video terminals; Processing a Connect message for connecting an IMG with an H.323 video terminal; And processing H.245 signaling for call setup between the H.323 terminal and the H.324M terminal, and establishing a call path between the H.323 terminal and the H.324M terminal.

According to the second aspect of the present invention, in the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network, when the representative number for the call between the H.323 video terminals is input from the H.324M video telephone, the CGS is IAM. Sending a message to the SG; Transmitting, by the SG, the received IAM message to the IMG in Sigtran; The IMG sends an admission request to the gatekeeper, and the gatekeeper sends an admission confirmation to the IMG; Requesting the IMG to set up a call to the IVR, connecting the call path between the H.324M terminal and the IVR; Requesting an announcement from the gatekeeper by the gatekeeper; Requesting the IVR to input a called number to the H.324M terminal; Transmitting, by the IVR, the called number received from the H.324M terminal to the gatekeeper, and releasing the call path with the H.324M terminal; A gatekeeper requesting setup from an H.323 terminal; Requesting, by the H.323 terminal, the gatekeeper for an admission and receiving confirmation; Setting up a call connection with the H.324M terminal by the H.323 terminal; The H.324M terminal and the IMG negotiating an error recovery degree; And a step in which the H.323 terminal and the H.324 terminal negotiate terminal capability, and a video call path is formed between the H.323 terminal and the H.324M terminal.

In the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network according to the third aspect of the present invention, when the H.323 video terminal number is input from the H.324M video terminal, the WCDMA HLR is routed to the CGS. ); Sending, by the CGS, an IAM message to the SG; Transmitting, by the SG, an IAM message received in Sigtran to an IMG; Sending, by the IMG, an admission request to the gatekeeper; The gatekeeper sending an admission confirm to the IMG; Sending, by the IMG, a Setup message to an H.323 terminal; Sending, by the H.323 terminal, a Call Processing message to the IMG; Sending, by the H.323 terminal, an admission request to the gatekeeper; Sending, by the gatekeeper, an admission confirmation to an H.323 terminal; Setting up, by the H.323 terminal, a call connection with the H.324M terminal; Performing a level nego to negotiate an error recovery degree between the IMG and the H.324M terminal; And negotiating terminal capability by the H.323 terminal and the H.324M terminal, and forming a video call path between the H.323 terminal and the H.324M terminal.

The video telephony interworking method between the WCDMA network and the CDMA2000 1X EV-DO network according to the present invention connects a call requested by an H.324M video terminal to an H.323 video terminal or vice versa. In this case, the connection to the IMG uses a method in which the gatekeeper (GK) or the WCDMA HLR has subscriber information of the counterpart system or requests the counterpart system to obtain the counterpart subscriber information, or in a special case, directly connects to the IMG.

In such a configuration, a video is obtained between a subscriber using an H.324M line type video telephone service provided in an asynchronous WCDMA network and a subscriber using an H.323 packet type video telephone service provided in a synchronous CDMA2000 1XEV-DO network. Calling is possible.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating an embodiment of a system for performing a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

In FIG. 1, a WCDMA network may be divided into a wireless network and a core network. The radio network (RAN) 102 is composed of a base station Node B and a radio network controller (RNC) that controls the radio network. The circuit core network is composed of MSC 104, which is a switch, Signaling Transfer Point (STP) 107, CGS 106, which is a gateway exchange, and HLR 108, which is a home location register. The WCDMA HLR 108 of FIG. 1 is an HLR that provides signaling by converting a GSM MAP to an ANSI41 MAP.

The CDMA2000 1X EV-DO network can be divided into a wireless network and a core network. The wireless network (AN) 112 is composed of a base station (ANTS) and a wireless network controller (ANC) that controls the wireless network, and performs a terminal authentication function. There is a wireless network authentication server (AN-AAA) 114. The packet core network consists of a packet data service network (PDSN) 118, a mobility manager (HA) 120 for managing mobility of Mobile IP, and a user authentication server (AAA) 116 for authenticating an access terminal user. In addition, there is a gatekeeper (GK) 126 for controlling the video telephony service corresponding to the MSC of WCDMA for the video telephony service.

In addition, a protocol converter (IMG; Interworking Media Gateway; 130), a signaling gateway (SG; 128), a media gateway for converting a protocol for providing a video telephony service between a WCDMA network and a CDMA1X EV-DO network A media gateway controller (MGC) 124 and an interactive voice response (IVR) 122 for providing announcement and delivering called number are used.

Interworking Media Gateway (IMG) 130 provides H.323 and H.324M protocol translation, Media Stream Translation, H.245 signaling conversion, Media transport signaling conversion, H A media gateway that functions as a .323 end point and H.324M terminal emulation.

IVR (Interactive Voice Response) 122 provides guide broadcasting and special functions from H.324M to H.323, and SG (Signaling Gateway) 128 is a standard SIGTRAN-based signaling system as a packet-based video telephone network and circuit. The ISUP signal interworking function between the base video telephone networks is performed, and the MGC (Media Gateway Controller) 124 performs the functions of the signaling gateway, the IVR 122, and the MG control.

2 is a diagram illustrating a video call call processing procedure from an H.323 video terminal to an H.324M video terminal according to an embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

When the power is turned on, the H.323 video terminal performs terminal authentication with the wireless network authentication server and registers with the gatekeeper through the RAS channel after completing Mobile IP registration with the HA (RRQ; 201). In this case, the gatekeeper to be registered may be set in advance in the terminal. Otherwise, the gatekeeper to be registered may be found by multicasting (gatekeeper.n-top.com or IP address) or GRQ (Gatekeeper Request). In other words, the latter sends a message such as "Who is my gatekeeper?" To the multicast address. The gatekeeper then registers the alias and IP address by sending an RRQ to the address sent to the Gatekeeper Confirm (GCF).

The gatekeeper transmits a confirm message to the corresponding terminal (RCF; 202). When the calling terminal attempts a video call, it sets and transmits gatekeeper-routed call signaling in the Admission Request (ARQ; 203).

The gatekeeper processes the H.225 message in the confirm message and finds the address of the called mobile terminal and transmits it to the calling terminal (ACF). H.225 handles call signaling such as admission control and connection establishment and makes packets of video, audio and data information. In addition, it synchronizes media.

This step can have several configurations: The first configuration is the case in which the gatekeeper has H.324M subscriber information or a separate common DB configuration. The gatekeeper finds the number of the called terminal directly in the subscriber table and transmits it to the calling terminal.

The second configuration is the case where the H.323 subscriber DB and the H.324M subscriber DB interoperate with each other. In the case of mutually interlocking with a separate DB, the gatekeeper managing the H.323 video terminal queries the H.324M video terminal database. Receive subscriber authentication. In this case, mutual interworking between DBs is required.

The third configuration is a case of routing to the corresponding IMG system unconditionally in the case of a specific prefix. If a specific prefix is connected to the corresponding IMG system unconditionally through the called number analysis on the call introduced into the gatekeeper system.

The calling terminal transmits an H.225 call signaling setup message to the gatekeeper (Gatekeeper-routed call signaling) (Setup; 205), and the gatekeeper transmits an H.225 call signaling setup message to the IMG system (Gatekeeper-routed call). signaling) (Setup 206).

The IMG system transmits the sigtran signal processing including the called number to the SG system (setup; 207), and the SG system performs the IAM signal processing to the signal processing element (CGS) of the ISUP network of the mobile circuit network (IAM; 208).

The CGS system attempts to connect to the H.324M terminal for modem connection (call connection attempt; 209), and sends an ANM message to the SG system when the H.324M terminal responds (ACM, ANM; 210).

The SG system processes the Sigtran message in response to the response of the H.324M terminal to the IMG system (sigtran 211), and a call path between the IMG system and the H.324M video terminal is formed.

The IMG system negotiates a level negotiation for error recovery between H.324M radio sections (H.223 Level negotiation; 213), and processes a Connect message, H.225 Calling Signaling, for connection between H.323 video terminals (connect; 214).

After processing H.245 Signaling for call setup between H.323 terminal and H.324M terminal (H.245 Signaling; 215), the call path goes from End to End between H.323 terminal and H.324M terminal. (Call 216).

H.245 performs capability exchange (defining characteristics of media stream to be transmitted). In addition, the logical channel signaling function manages the end-to-end logical channel. Other functions include flow control of messages.

3 is a diagram illustrating a video call call processing procedure from an H.324M video terminal to an H.323 video terminal according to an embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

This embodiment is a case in which a call request from an H.324M video terminal is connected to an IMG using a special number, and when a representative number (special number) is dialed for a call between H.323 video terminals (representative number input; 301). When a 324M videophone subscriber dials a representative number (special number) for a call between H.323 video terminals (enter number; 301), the CGS exchange sends an IAM message to the SG system for ISUP signaling processing (IAM; 302). ).

The SG system sends the received IAM message in Sigtran to the IMG system (Sigtran; 303), the IMG sends an ARQ (Admission Request) to the gatekeeper (ARQ; 304), and the gatekeeper sends an ACF to the IMG. (ACF; 305).

The IMG requests the IVR to set up a call and the call path is connected between the H.324M terminal and the IVR. IMG requests setup to MGC (setup; 306), MGC requests MGC connection to IVR (MGC connection request; 307), IVR ACKs (Ack; 308) and MGC connects (Connect; 309). A call path is connected between the 324M terminal and the IVR.

The gatekeeper requests an announcement to the IVR (information broadcast request; 310). The IVR requests the input of the called party number to the H.324M terminal (called party number input request; 311), receives the input (called party number input; 312), and delivers it to the gatekeeper (called party number forwarding; 313), and then releases the call path. (Channel release) 314.

The gatekeeper requests a setup from the H.323 terminal (Setup; 315), and the H.323 terminal receives a confirmation by requesting an admission from the gatekeeper (ARQ; 316) (ACF; 317).

The H.323 terminal sets up a call connection with the H.324M terminal. The setup process is as follows. Step H.323 UE sends an alert to IMG (Alert; 318), IMG carries an Alert message to Sigtran and sends it to SG (Sigtran; 319), and SG delivers an ACM message to CGS (ACM; 320). . Again, the H.323 terminal sends a Connect message to the IMG to connect the call (Connect; 321), and the IMG carries the Connecting message to the Sigtran to the SG (Sigtran; 322), and the SG sends an ANM message to the CGS. Forward (ANM) 323. The CGS sets up a call connection between the H.323 terminal and the H.324M terminal by transmitting a Connect message to the H.324M terminal (Connect; 324).

The H.324M terminal and the IMG negotiate the degree of error recovery (Level Nego; 325).

H.323 UE and H.324 UE negotiate UE Capability using H.245 Control Signaling (H.245 Control Signaling; 326), and a video call path is formed between H.323 UE and H.324M UE ( Currency; 327).

4 is a diagram illustrating a video call call processing procedure from an H.324M video terminal to an H.323 video terminal in another embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention.

In this embodiment, the WCDMA HLR has a database of H.323 video terminals, and the H.323 video telephone subscriber information and the H.324M video telephone subscriber information are provided to the WCDMA HLR and the gatekeeper in the customer information center of the mobile carrier, respectively. do.

When an H.324M videophone subscriber dials an H.323 videophone number (enter number; 401), the MSC queries the WCDMA HLR (402-1) and the H.323 videophone subscriber received by the WCDMA HLR from the customer information center. If the WCDMA HLR confirms that it is an H.323 video terminal when inquiring about the called party information, it responds with a routing number to be connected to the CGS capable of IMG connection to the MSC (402-2), and the MSC allocates a line to the corresponding CGS again. (402-3) Perform the number translation procedure.

The CGS sends an IAM message to the SG system for ISUP Signaling processing (IAM; 403), and the SG system transmits the received IAM message to the IMG system in Sigtran (Sigtran; 404).

The IMG sends an ARQ (Admission Request) to the gatekeeper (ARQ; 405), and the gatekeeper sees the H.324M videophone subscriber information received from the customer information center and sends an Admission Confirm to the IMG (ACF; 406).

The IMG sends a Setup message to the H.323 terminal through the gatekeeper (Setup; 407, Setup; 408), and the H.323 terminal sends a Call Processing message to the IMG through the gatekeeper (Call processing; 409). 410).

The H.323 terminal sends an Admission Request to the gatekeeper (ARQ; 411), and the gatekeeper sees the H.323 videophone subscriber information received from the customer information center and sends an Admission Confirm to the H.323 terminal (ACF; 412).

The H.323 terminal sets up a call connection with the H.324M terminal. The procedure is as follows. The H.323 terminal sends an Alerting message to the IMG via the gatekeeper (Alerting; 413, Alerting; 414). IMG carries an Alerting message in Sigtran and delivers it to SG (Sigtran; 415), and SG delivers an ACM message to CGS (ACM; 416). The H.323 terminal sends a Connecting message to the IMG through the gatekeeper to connect the call (Connecting; 417, Connecting; 418). The IMG carries the Connecting message to the Sigtran and sends it to the SG (Sigtran; 419), the SG delivers the ANM message to the CGS (ANM; 420), and the CGS delivers the Connect message to the H.324M terminal (Connect; 421). ).

Level Nego negotiates the level of error recovery between IMG and H.324M terminals (H.223 Level Nego; 422), and H.323 terminals and H.324M terminals use H.245 Control Signaling By negotiating (H.245 Control Signaling) 423, a video call path is formed between the H.323 terminal and the H.324M terminal (call 424).

5 is a diagram illustrating an IMG protocol stack in an embodiment of a video phone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network according to the present invention. In FIG. 5, a part of processing voice and video traffic, a part related to H.324M signaling and H.323 signaling, are shown.

In this way, video calls are processed between H.324M based video terminals and H.323 based video terminals using different protocols.

According to the present invention, a video call between a subscriber using an H.324M line type video telephone service provided in an asynchronous WCDMA network and a subscriber using an H.323 packet type video telephone service provided in a synchronous CDMA2000 1XEV-DO network. Is realized.

Although the invention has been described in terms of preferred embodiments, the scope of the invention should not be limited thereto, but will also extend to the variations and improvements supported by the claims.

Claims (11)

(1) if an admission request is sent from the H.323 video terminal, the gatekeeper sending an H.225 call signal setup message to the IMG; (2) the IMG transmitting sigtran signal processing including the called number and the like to the SG; (3) the SG performing IAM signal processing on a CGS of a mobile circuit; (4) the CGS attempting to make a call connection for a modem connection of an H.324M terminal, and transmitting an ANM message to the SG when the H.324M terminal responds; (5) the SG processing a Sigtran message in response to the H.324M terminal with an IMG; (6) a call path is formed between the IMG and the H.324M, and the IMG negotiates a level negotiation for error recovery between the H.324M video terminals; (7) processing a Connect message for connecting the IMG with the H.323 video terminal; And (8) processing H.245 signaling for call setup between the H.323 terminal and the H.324M terminal, and establishing a call path between the H.323 terminal and the H.324M terminal. A video telephone interworking method between a WCDMA network and a CDMA2000 1X EV-DO network. According to claim 1, wherein step (1), (A) when an admission request is transmitted from the H.323 video terminal, the gatekeeper finding an address of the H.324M video terminal and transmitting the address to the H.323 video terminal; And (B) when the H.225 call signaling setup message is transmitted from the H.323 video terminal to the gatekeeper, the gatekeeper transmits an H.225 call signal setup message to the IMG. Video telephony interworking method between network and CDMA2000 1X EV-DO network. The method of claim 2, wherein (a) comprises: And the gatekeeper directly finds the address of the H.324M video terminal in a database and transmits the address to the H.323 video terminal. The method of claim 2, wherein step (a) The gatekeeper receives the address of the H.324M video terminal from the database of the H.324M system and transmits to the H.323 video terminal to the video call interworking method between the WCDMA network and CDMA2000 1X EV-DO network . According to claim 1, wherein step (1), When an Admission Request is transmitted from the H.323 video terminal, all incoming calls to the gatekeeper are connected to the corresponding IMG system in the case of a predetermined prefix through caller number analysis. Video telephony interworking between WCDMA network and CDMA2000 1X EV-DO network. (1) when the representative number for the call between the H.323 video terminals is input from the H.324M video telephone, the CGS sending an IAM message to the SG; (2) the SG transmitting the received IAM message to the IMG in Sigtran; (3) the IMG sends an admission request to a gatekeeper, and the gatekeeper sends an admission confirmation to the IMG; (4) the IMG requesting setup of a call to the IVR to connect a call path between the H.324M terminal and the IVR; (5) the gatekeeper requesting announcement to the IVR; (6) the IVR requesting input of a called number to the H.324M terminal; (7) the IVR transferring the called number received from the H.324M terminal to the gatekeeper, and releasing the call path with the H.324M terminal; (8) the gatekeeper requesting a setup from the H.323 terminal; (9) the H.323 terminal requesting an admission to the gatekeeper and receiving a confirmation; (10) installing, by the H.323 terminal, a call connection with the H.324M terminal; (11) negotiating an error recovery degree between the H.324M terminal and the IMG; And (12) the WCDMA network and the CDMA2000, wherein the H.323 terminal and the H.324 terminal negotiate terminal capability and a video call path is formed between the H.323 terminal and the H.324M terminal. How to link video calls between 1X EV-DO networks. According to claim 6, wherein step (4), The IMG requesting setup from the MGC; The MGC requesting MGC connection to the IVR, and the IVR ACKing; And And transmitting, by the MGC, the Connect message to the H.324M terminal, the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network. According to claim 6, wherein step (10), Sending an alert to the IMG by the H.323 terminal; The IMG sending a Sigtran to the SG; The SG sends an ACM to the CGS; Transmitting, by the H.323 terminal, a Connect message to the IMG; The IMG loading a Connect message to Sigtran and delivering to the SG; The SG forwarding an ANM message to the CGS; And And transmitting, by the CGS, the Connect message to the H.324M terminal, the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network. (1) when the H.323 video terminal number is input from the H.324M video terminal, the WCDMA HLR routing to the CGS; (2) the CGS sending an IAM message to an SG; (3) transmitting, by the SG, the received IAM message to IMG in Sigtran; (4) the IMG sending an admission request to the gatekeeper; (5) the gatekeeper sending an admission confirmation to the IMG; (6) the IMG sending a Setup message to the H.323 terminal; (7) the H.323 terminal sending a Call Processing message to the IMG; (8) the H.323 terminal sending an admission request to the gatekeeper; (9) the gatekeeper sending an admission confirmation to the H.323 terminal; (10) installing, by the H.323 terminal, a call connection with the H.324M terminal; (11) performing Level Nego to negotiate the degree of Error Recovery between the IMG and the H.324M terminal; And (12) WCDMA network and the H.323 terminal and the H.324M terminal negotiating terminal capability, and the video call path is formed between the H.323 terminal and the H.324M terminal and Video telephony interworking between CDMA2000 1X EV-DO network. 10. The WCDMA network and CDMA2000 1X EV-DO of claim 9, wherein the H.323 video terminal subscriber information and the H.324M video terminal subscriber information are provided to the WCDMA HLR and the gatekeeper at the customer information center. How to link video calls between networks. The method of claim 9, wherein step (10) comprises: Sending, by the H.323 terminal, an Alerting message to the IMG; Sending, by the IMG, an Alerting message to Sigtran to SG; The SG forwarding an ACM message to CGS; Transmitting, by the H.323 terminal, a Connecting message to the IMG; Sending, by the IMG, a Connecting message to Sigtran and transmitting to SG; The SG forwarding an ANM message to the CGS; And And transmitting, by the CGS, the Connect message to the H.324M terminal, the video telephone interworking method between the WCDMA network and the CDMA2000 1X EV-DO network.