KR101050576B1 - Method and system for providing video conferencing service between mobile terminals of heterogeneous networks - Google Patents

Abstract

The present invention relates to a method and a system for providing a video conference service between mobile terminals of heterogeneous networks. In a communication system comprising a, a method for providing a video conferencing service, comprising: establishing a video conferencing room by the video conferencing server as the terminal of the IP network is connected; Receiving, by the exchange of the IP network, an invitation message based on a Session Initiation Protocol (SIP) for inviting a called terminal from a terminal of the IP network; Checking, by the switch of the IP network, whether the called terminal is a terminal of a circuit switched network; When the called terminal is a terminal of a circuit switched network, sending, by the exchange of the IP network, the invitation message to the gateway; Establishing, by the gateway, a primary session in the video conference room upon receipt of the invitation message; Converting, by the gateway, the invitation message into an ISDN (ISDN User Part) message of the circuit switched network, and transmitting the converted ISUP message to the called terminal to establish a secondary session with the called terminal; And interconnecting, by the gateway, a primary session with the video conference room and a secondary session with the called terminal.

The present invention has an advantage of increasing the versatility of a multi-party video conferencing service by providing a process for allowing a SIP supporting terminal of an IP network to participate in a video conference of a SIP non-supporting terminal of another network.

SIP, ISUP, Invitation Message, Signaling Gateway, Video Conferencing

Description

Method and system for providing video conferencing service between mobile terminals of heterogeneous networks {SYSTEM AND METHOD FOR PROVIDING VIDEOCONFERENCE SERVICE BETWEEN MOBILE COMMUNICATION TERMINALS IN HETEROGENEOUS NETWORK}

The present invention relates to a videoconferencing service providing technology in a mobile communication system, and more particularly, to a method and system for providing a videoconferencing service between mobile terminals connected to heterogeneous networks in a mobile communication system.

Today, due to the development of mobile communication networks and wireless communication devices, users are provided with more various services using mobile terminals. For example, users are provided with a messenger service, a video call service, a wireless internet service, an on-line game service, etc. in addition to a voice call.

It provides a variety of services at high speed and is based on IP protocol for voice, audio, and video. Commercialization of IMS (IP Multimedia Subsystem) network which supports multimedia etc. complexly is progressing. The IMS is able to provide various contents at the same time and is easy to expand, which is attracting attention as a next generation communication network. The IMS network provides various services to the mobile terminal by transmitting and receiving a message based on Session Initiation Protocol (SIP).

Representative among the services provided by the IMS network to the user is a multi-party video conferencing service. Looking at the process of video conferencing service through the IMS network, the calling terminal opens a video conference room and transmits a SIP-based video conference invitation message inviting the called terminal to the video conference room. A representative example of such a SIP-based video conference invitation message is a REFER message proposed by the Internet Engineering Task Force (IETF), an international standards organization. The REFER message is a message indicating a specific action to a specific terminal or server, and the calling terminal induces the called terminal to be connected to the video conference room by transmitting the REFER message. Then, the called terminal accesses the video conference room based on the REFER message, and then the video conference is performed between the calling terminal and the called terminal. That is, according to the current international standard, a calling terminal which has opened a video conference room transmits a REFER message, which is a video conference invitation message, so that the called terminal accesses the video conference room based on the REFER message.

As described above, in order to induce participation in the IMS-based video conference, a SIP-based video conference invitation message should be transmitted to the terminal of the conference target. However, when the called terminal is a terminal connected to a circuit switched network without accessing an IMS network, the called terminal cannot interpret a video conference invitation message. That is, when the terminal for which the video conference is established is a SIP-enabled terminal and the called terminal invited to the video conference is a non-SIP terminal, even if the calling terminal transmits the video conference invitation message, the called terminal interprets the SIP-based video conference invitation message. There is a problem that can not respond to the invitation to the video conference.

Meanwhile, a method of providing a video conference service between heterogeneous terminals using another type of SIP message without using an invitation message of an international standard has been disclosed. However, the above method uses a different type of SIP message instead of the REFER message, which is an international standard, so that the application scope of the video conferencing service is narrowed because it is applicable only to its own terminal without interworking with other operator terminals. There is this.

SUMMARY OF THE INVENTION The present invention has been proposed to solve these conventional problems, and an object thereof is to provide a method and system for providing a smooth video conferencing service between mobile terminals respectively connected to an IP network and a circuit switched network.

Another object of the present invention is to provide a method and system for providing a video conferencing service between heterogeneous mobile terminals using an invitation message of an international standard that can interoperate with a terminal of another operator.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. Also, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

In accordance with a first aspect of the present invention for achieving the above object, a communication configured to include a switch of an IP (Internet Protocol) network, a video conferencing server, a switch of a circuit switched network, and a gateway for interworking of the IP network and a circuit switched network. In the system, a method of providing a video conferencing service, the method comprising: (a) the video conferencing server to open a video conferencing room as the terminal of the IP network is connected; (b) receiving, by the exchange of the IP network, an invitation message based on a Session Initiation Protocol (SIP) inviting a called terminal from a terminal of the IP network; (c) checking, by the exchange of the IP network, whether the called terminal is a terminal of a circuit switched network; (d) when the called terminal is a terminal of a circuit switched network, sending, by the exchange of the IP network, the invitation message to the gateway; (e) establishing, by the gateway, a primary session in the video conference room upon receipt of the invitation message; (f) the gateway converting the invitation message into an ISDN (ISDN User Part) message of the circuit switched network, and transmitting the converted ISUP message to the destination terminal to establish a secondary session with the destination terminal; And (g) interconnecting, by the gateway, a primary session with the video conference room and a secondary session with the called terminal.

According to a second aspect of the present invention for achieving the above object, a videoconferencing providing system for providing a videoconferencing service in interworking of an IP (Internet Protocol) network and a circuit-switching network is provided as a terminal of the IP network connects. Video conferencing server to outline a room; A switch of an IP network which receives a Session Initiation Protocol (SIP) based invitation message inviting a called terminal from the terminal of the IP network and checks whether the called terminal is a terminal of the circuit switched network; And when the called terminal is a terminal of a circuit switched network, receives the invitation message from a switch of the IP network, sets up a primary session in the video conference room according to the invitation message, and sends the invitation message to the circuit switched network. And converting it into an ISUP (ISDN User Part) message and transmitting it to the called terminal to establish a secondary session, wherein the gateway connects the primary session and the secondary session to each other.

The present invention has an advantage of increasing the versatility of a multi-party video conferencing service by providing a process for allowing a SIP supporting terminal of an IP network to participate in a video conference of a SIP non-supporting terminal of another network.

In particular, the present invention has an advantage of smoothly proceeding video conferencing service between heterogeneous terminals by converting and sending a SIP-based video conferencing invitation message into an ISUP-based message that can be interpreted by a circuit-switching terminal.

In addition, the present invention provides a video conferencing service between heterogeneous mobile terminals based on an invitation message of an international standard, thereby providing a video conferencing service regardless of the operator and extending the application range of the video conferencing service. .

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings, in which: There will be. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a configuration of a system for providing a video conference service between terminals connected to heterogeneous networks of the same operator according to an embodiment of the present invention.

As shown in FIG. 1, a video conferencing system according to a preferred embodiment of the present invention includes a circuit switch 131, a home subscriber server (HSS) 141, a call session control function (CSCF), and a video conferencing server ( 145) and a signaling gateway 150. The circuit switch 131 is located in a circuit switching network (hereinafter referred to as a “CS network”) 130 and the HSS 141, the CSCF 143, and the video conferencing server 145 are located in the IP network 140. Located. The CS network 130 includes a WCDMA network and a CDMA network, and sets up a voice / video call with the mobile terminal 110 using an ISUP (ISDN User Part) based message. In addition, the IP network 140 includes an IP Multimedia Subsystem (IMS) network and a General Packet Radio Service (GPRS) network, and uses a SIP (Session Initiation Protocol) based message to communicate with the mobile terminal 120 of the IP network. / Set video call.

Circuit switching terminal (hereinafter referred to as "CS terminal", 110) is connected to the CS network 130, and receives a mobile communication service, such as video / audio call. In particular, the CS terminal 110 establishes a video / audio call by transmitting and receiving an ISUP-based message with the CS network 130.

A terminal supporting SIP (hereinafter, referred to as a "SIP terminal") 120 is connected to the IP network 140 to receive services such as video / audio call and presence service, and in particular, the IP network 140 and the SIP-based Send and receive messages. That is, the SIP terminal 120 communicates with the IP network 140 using messages such as INVITE, REFER, 180 Ringing, 200 OK, and 202 Accepted, which are SIP-based messages.

The circuit switch 131 establishes a voice / video call with the CS terminal 110 through an ISUP-based message and provides a communication service to the corresponding CS terminal 110. Specifically, the circuit switch 131 establishes a video / audio call with the CS terminal 110 by using an ISUP-based message, IAM (Address Complete Message), ACM (Answer Message), or the like. do.

The HSS 141 stores profile information and location information for each of the mobile terminals 110 and 120. In particular, the HSS 141 stores information on whether the network to which the mobile terminals 110 and 120 belong is its own provider network or another provider network, and in the case of its own network, type information of the network (ie, CS network or IP network).

The videoconferencing server 145 establishes a videoconferencing room and transmits videoconferencing data (ie, image data and audio data) to a plurality of mobile terminals 110 and 120 connected to the videoconferencing room.

The CSCF 143 is a kind of exchange device located in the IP network 140 and processes the SIP message. The CSCF 143 includes a proxy-call session control function (P-CSCF), a serving-call session control function (S-CSCF), and an interrogating-call session control function (IC-CSCF).

In particular, when the CSCF 143 receives a SIP-based message inviting the other mobile terminals 110 and 120 from the SIP terminal 120 which has established a video conference, the CSCF 143 receives the location information of the invited mobile terminals 110 and 120. Acquired through the HSS 141, and transmits a video conference invitation message to the signaling gateway 150 or the mobile terminal (110, 120) to be invited based on the obtained information.

The signaling gateway 150 connects the CS network 130 and the IP network 140, converts the SIP message transmitted from the IP network 140 into an ISUP message, and transmits it to the CS network 130. In addition, the signaling gateway 150 converts the ISUP message received from the CS network 130 into a SIP message and transmits it to the IP network 140. In particular, when the signaling gateway 150 receives the SIP-based video conference invitation message from the CSCF 143 of the IP network 140, the signaling gateway 150 uses the method included in the invitation message to establish a primary session with the video conference server 145. And convert the SIP-based invitation message into an ISUP-based message commonly used in the CS network 130 and use the converted message to establish a secondary session with the CS terminal 110 connected to the CS network 130. Set. In addition, the signaling gateway 150 interconnects the primary session and the secondary session, thereby connecting the SIP terminal 120 connected to the IP network 140 and the CS terminal 110 connected to the CS network 130. Proceed with video conference.

2 is a flowchart illustrating a method of providing a video conference service between a SIP terminal and a CS terminal belonging to the same operator network in a mobile communication system according to an embodiment of the present invention.

Referring to FIG. 2, the SIP terminal 120 of the IP network 140 connects to the video conference server 145 to establish a video conference room, and sets up the opened video conference room and session (S201). Next, the SIP terminal 120 receives an operation signal for inviting a specific terminal from the user (S203). Then, the SIP terminal 120 generates a REFER message which is a video conference invitation message of the international standard inviting the terminal and transmits it to the CSCF 143 (S205). The REFER message is a message indicating an action for a specific terminal or a specific server. A URI (Uniform Resource Identifier) of the established video conference room is recorded in a "Refer to" field of the REFER message, and a "Method" field. INVITE is recorded. That is, the REFER message is a message for instructing the terminal or server to connect to the address of the video conference room recorded in the "Refer to" field using the INVITE message recorded in the "Method" field.

Upon receiving the REFER message, the CSCF 143 transmits a location information request message to which the identifier (i.e., IMSI or identification number) of the invite terminal is added to the HSS 141, and includes the called network type information in response thereto. The location information of the called terminal (that is, the invitation target terminal) is received (S207 and S209). Next, the CSCF 143 checks the network type to which the called terminal is connected based on the received location information, and if the network type is the IP network 140, transmits a REFER message to the IP network 140 (S211). , S213).

On the contrary, if the network to which the called terminal is connected is the CS network 130, the CSCF 143 transmits a REFER message, which is a video conference invitation message, to the signaling gateway 150 (S215). The CSCF 143 receives the 202 Accepted message from the signaling gateway 150, which means that the REFER message is normally received, and transmits the 202 Accepted message to the SIP terminal 120 (S217). Accordingly, the SIP terminal 120 recognizes that the REFER message for inviting the called terminal to the video conference room has been normally received from the IP network 140.

Upon receiving the REFER message, the signaling gateway 150 transmits an INVITE message to the videoconferencing server 145 based on the information recorded in the "Method" field and the "Refer to" field of the REFER message (S219). That is, the signaling gateway 150 transmits the INVITE message recorded in the "Method" field of the REFER message to the URI (ie, the video conference room) of the "Refer to" field. Then, the video conferencing server 145 proceeds with session setting with the signaling gateway 150 according to the reception of the INVITE message, and sends a 180 ringing message via the CSCF 143 indicating that the session is in progress. Transfer to 150 (S221). Subsequently, when the session setup is completed, the video conferencing server 145 transmits a 200 OK message to the signaling gateway 150 via the CSCF 143 (S223). Then, the signaling gateway 150 accesses the video conference room opened by the SIP terminal 120 in step S201 through the set session (S225).

The signaling gateway 150 setting up the video conference room and session converts a SIP-based REFER message into an ISUP-based IAM (Initial Address Message) in order to join a called terminal belonging to a CS network 130 to the video conference room. And transmits to the circuit exchange 131 to which the called terminal is connected (S227). That is, since the signaling gateway 150 cannot interpret the SIP-based REFER message in the CS terminal 110, the signaling gateway 150 converts the REFER message into an ISUP-based message and transmits the REFER message to the circuit switch 131 of the called terminal identified in step S209. .

Then, the circuit switch 131 transmits a paging signal through the base station controller and the base station that manages the destination terminal according to the IAM reception, and receives a paging response from the destination terminal (S229 and S231). Next, the circuit switch 131 transmits an address complete message (ACM) indicating that the called terminal is ready for video call setup to the signaling gateway 150 (S233). Subsequently, the circuit switch 131 receives an ACK message, which is a connection response to the video call, from the called terminal, and transmits an ISUP based ANM (Answer Message) to the signaling gateway 150 (S235 and S237).

Then, the signaling gateway 150 establishes a session for the video call with the called terminal through the circuit switch 131 (S239). Subsequently, the signaling gateway 150 connects the session set up in step S225 and the session set up in step S239 to connect the called terminal, which is the CS terminal 110, to the opened video conference room (S241). Accordingly, the SIP terminal 120 having opened the video conference room and the CS terminal 110 which is the called terminal invited to the video conference are connected to the video conference server 145 to perform the video conference.

On the other hand, the HSS 141 typically only stores the type information of the network belonging to its own provider, and does not store the network type information of other operators. In other words, when the HSS 141 receives the location information request of the called terminal from the CSCF 143, when the network connected to the called terminal is its own network, the HSS 141 may provide the type information of the access network to the CSCF 143. Only, the network type information may not be provided to the CSCF 143 when the access network of the called terminal is a third party network.

Therefore, the CSCF 143 needs to grasp the access network of the called terminal even when the called terminal is connected to another provider network.

3 is a diagram illustrating a configuration of a system for providing a video conference service between terminals connected to heterogeneous networks of different operators according to another embodiment of the present invention.

Hereinafter, since components having the same reference numerals as those of FIG. 1 in FIG. 3 play the same role as the components of FIG. 1, detailed descriptions thereof will be omitted.

As shown in FIG. 3, the videoconferencing providing system according to the preferred embodiment of the present invention includes a circuit switch 131, a home subscriber server (HSS) 141, a call session control function (CSCF), and a videoconferencing server ( 145, a signaling gateway 150, and a provider management server 147, wherein the component belongs to the A provider network 100. In addition, the B provider network 200 includes the CS network 230, the C provider network 300 includes an IP network 330. Each of these provider networks 100, 200, and 300 are connected to each other through a network infrastructure to communicate.

The operator management server 147 stores the type information of the communication network for each switch ID of another operator network. That is, the operator management server 147 stores network type information such as the IP network 330 and the CS network 230 in response to the exchange ID of the third party network. For example, the operator management server 147 stores the IP network 330 information corresponding to the exchange 333 ID of 0x12A13FF belonging to the C operator network 300, and the exchange 231 of 3x12B323F belonging to the B operator network 200. CS network information 230 may be stored corresponding to the ID.

Meanwhile, the CSCF 143 obtains the access network type information of the invited target terminal connected to its provider network 100 through the HSS 141, and checks the access target terminal of the invited target terminal connected to other provider networks 200 and 300. Network type information is obtained through the operator management server 147. In addition, the CSCF 143 determines the transmission path of the SIP-based invitation message based on the obtained network type.

4 is a flowchart illustrating a method for providing a video conference service between a SIP terminal and a CS terminal belonging to different operator networks in a mobile communication system according to another embodiment of the present invention.

In the description with reference to FIG. 4, portions overlapping with the description with reference to FIG. 2 will be summarized and described based on differences.

Referring to FIG. 4, the SIP terminal 120 of the A-company network 100 having opened a video conference room through the video conference server 145 receives a REFRE message for inviting other terminals according to a user's operation. (S401, S403, S405).

Then, the CSCF 143 transmits the location information request message of the inviting target terminal to the HSS 141, and in response thereto, the location of the called terminal (that is, the inviting target terminal) including the ID of the called exchange and the called network information. Information is received (S407, S409). At this time, the CSCF 143 receives the type information (ie, information such as CS network, IP network) of the network as the destination network information from the HSS 141 when the network to which the destination terminal is connected is the company network 100, If the third-party vendor network (200, 300) receives only the other carrier information except the type information of the network as the destination network information. That is, the CSCF 143 indicates that the destination exchanger ID and the destination terminal are connected to the other provider network 200, 300 from the HSS 141 when the destination terminal is connected to the other provider network 200, 300. Receive the information indicated.

Next, the CSCF 143 confirms that the called terminal is connected to other provider networks 200 and 300 based on the location information of the called terminal obtained from the HSS 141 (S411). Accordingly, the CSCF 143 requests the type information of the third-party network 200 or 300 by transmitting the ID of the destination exchange received in step S409 to the operator management server 147 (S413). Then, the operator management server 147 extracts network type information of other operators 200 and 300 corresponding to the received exchanger ID and transmits it to the CSCF 143 (S415). That is, the CSCF 143 checks the type of the network based on the location information obtained from the HSS 141 when the access network of the called terminal is its provider network 100. On the other hand, the CSCF 143 checks the network type of the called terminal through the operator management server 147 if the network connected to the called terminal is another operator's network (200, 300).

As described above, the CSCF 143 that receives the network type information accessed by the called terminal checks whether the network is an IP network 330 of a third party vendor, and if the IP network 330 is a REFER to the IP network 330. The message is transmitted (S417, S419). That is, when the called terminal accesses the IP network 330 of the other company, the CSCF 143 transmits a REFER message to the CSCF 333 of the other company, and finally the REFER message is received through the corresponding CSCF 333. 310 to be delivered.

On the other hand, the CSCF 143 transmits a REFER message to the signaling gateway 150 when the network to which the called terminal is connected is not the IP network 330 of the other operator but the CS network 230 of the other operator, and in response thereto, 202. The receiver receives the accepted message and transmits the called terminal to the invited SIP terminal 120 (S421 and S423).

Next, the signaling gateway 150 transmits the INVITE message to the videoconferencing server 145 based on the information recorded in the "Method" field and the "Refer to" field of the REFER message (S425). Then, in response to receiving the INVITE message, the video conferencing server 145 proceeds with session establishment with the signaling gateway 150 and sends a 180 ringing message through its CSCF 143 indicating that the session establishment is in progress. The signaling gateway 150 transmits the signal to the signaling gateway 150 (S427). Subsequently, when the session setup is completed, the video conferencing server 145 transmits a 200 OK message to the signaling gateway 150 via its CSCF 143 (S429). Then, the signaling gateway 150 accesses the video conference room opened by the SIP terminal 120 in step S201 through the set session (S431).

The signaling gateway 150 that sets up the video conference room and session transmits a SIP-based REFER message to the ISUP-based IAM (Initial) in order to join the called terminal 210 belonging to the CS network 230 of another company to the video conference room. Address message) and transmits it to the circuit switch 231 to which the called terminal 210 is connected (S433). Then, the circuit switch 231 of the third party transmits a paging signal to the destination terminal 210 according to the IAM reception, receives a paging response, and transmits an address complete message (ACM) to the signaling gateway 150 ( S435, S437, S439). Next, the circuit switch 231 of the other party receives an ACK message, which is a connection response to the video call, from the destination terminal 210 and transmits an ISUP based ANM (Answer Message) to the signaling gateway 150 (S441 and S443). ).

Then, the signaling gateway 150 establishes a session for the video call with the destination terminal 210 through the circuit switch 231 of the third party (S445). The signaling gateway 150 interconnects the session set in step S431 and the session set in step S445 to connect the called terminal 210 connected to the CS network 230 of the third party to a video conference room (S447). . Accordingly, the SIP terminal 120 of the company which opened the video conference room and the CS terminal 210 which is the called terminal of the other party invited to the video conference are connected to the video conference server 145 to perform the video conference.

As described above, the present invention has an advantage of increasing the versatility of the video conferencing service by providing a process in which the SIP terminal 120 can invite the CS terminals 110 and 210. That is, in the related art, the CS terminals 120 and 210 that have received the SIP-based invitation message cannot participate in the video conference. However, the present invention provides the CS terminals 110 and 210 to send the SIP-based invitation message through the signaling gateway 150. By converting into an ISUP-based message that can be interpreted by the CS terminal (110, 210) is normally involved in the video conference. In particular, since the present invention provides a video conference service between heterogeneous mobile terminals based on the REFER message, which is an invitation message of an international standard, it is possible to interwork with terminals 210 and 310 of other operators, thereby extending the scope of the video conference service. There is this.

While this specification contains many features, such features should not be construed as limiting the scope of the invention or the claims. Also, the features described in the individual embodiments herein can be implemented in combination in a single embodiment. Conversely, various features described in a single embodiment herein can be implemented individually in various embodiments or in combination as appropriate.

Although the operations are described in a particular order in the drawings, they should not be understood as being performed in a particular order as shown, or in a sequence of successive orders, or all described actions being performed to obtain a desired result. . In certain circumstances, multitasking and parallel processing may be advantageous. In addition, it should be understood that the division of various system components in the above-described embodiments does not require such division in all embodiments. The above-described program components and systems can generally be implemented as a single software product or as a package in multiple software products.

The method of the present invention as described above may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form. Since this process can be easily implemented by those skilled in the art will not be described in more detail.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

The following drawings, which are attached to this specification, illustrate exemplary embodiments of the present invention, and together with the detailed description of the present invention, serve to further understand the technical spirit of the present invention. It should not be construed as limited to.

1 is a diagram illustrating a configuration of a system for providing a video conference service between terminals connected to heterogeneous networks of the same operator according to an embodiment of the present invention.

2 is a flowchart illustrating a method of providing a video conference service between a SIP terminal and a CS terminal belonging to the same operator network in a mobile communication system according to an embodiment of the present invention.

3 is a diagram illustrating a configuration of a system for providing a video conference service between terminals connected to heterogeneous networks of different operators according to another embodiment of the present invention.

4 is a flowchart illustrating a method of providing a video conference service between a SIP terminal and a CS terminal belonging to different operator networks in a mobile communication system according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

131, 231: circuit exchange 141: HSS

143, 333: CSCF 145: video conferencing server

147: Operator Management Server 150: Signaling Gateway

Claims (12)

In a communication system including a switch of an Internet Protocol (IP) network, a video conference server, a switch of a circuit switched network, and a gateway for interworking with the IP network and a circuit switched network, a method of providing a video conference service is provided. (a) establishing, by the video conference server, a video conference room as a terminal of the IP network is connected; (b) the exchange of the IP network receiving a REFER message from a terminal of the IP network, in which an INVITE message is recorded in a method field and a Uniform Resource Identifier (URI) of the video conference room is recorded in a refer to field; (c) checking, by the exchange of the IP network, whether the called terminal, which is the invite terminal, is a terminal of the circuit switched network; (d) when the called terminal is a terminal of a circuit switched network, sending, by the exchange of the IP network, the REFER message to the gateway; (e) the gateway confirming an INVITE message and a URI recorded in each field of the REFER message, and transmitting the INVITE message to the URI to establish a primary session with the video conference room; (f) the gateway converting the REFER message into an IDN (ISDN User Part) message of the circuit switched network, and transmitting the converted ISUP message to the destination terminal to establish a secondary session with the destination terminal; And and (g) interconnecting, by the gateway, a first session with the video conference room and a second session with the called terminal. The method of claim 1, In step (c), (c-1) acquiring, by the exchange of the IP network, network type information to which the called terminal is connected; And (c-2) checking, by the switch of the IP network, whether the called terminal is a terminal of the circuit switched network, based on the obtained network type information. The method of claim 2, Step (c-1), Obtaining, by the exchange of the IP network, location information of the called terminal; And And extracting, by the exchange of the IP network, network type information included in the obtained location information. The method of claim 1, In step (c), (c-1) checking, by the exchange of the IP network, whether the access network of the called terminal is another provider network; And (c-2) if the other operator's network, the exchange of the IP network, from the operator management server to determine whether the other operator's network is a circuit-switched network; video conferencing service providing method comprising a. The method of claim 4, wherein Step (c-2), Transmitting, by the exchange of the IP network, identification information of the called exchange to the operator management server; And And receiving, by the exchange of the IP network, the network type information corresponding to the identification information from the operator management server. delete A video conference providing system that provides a video conference service in the interworking of an IP (Internet Protocol) network and a circuit switched network. A video conference server for opening a video conference room as the terminal of the IP network is connected; An INVITE message is recorded in the method field, and a REFER message in which the URI (Uniform Resource Identifier) of the video conference room is recorded in the refer to field is received from the terminal of the IP network. An exchange of an IP network to confirm; And When the called terminal is a terminal of a circuit switched network, the REFER message is received from the switch of the IP network, the INVITE message and the URI recorded in each field of the REFER message are checked, and the INVITE message is transmitted using the URI. Set up a primary session with the video conference room, convert the REFER message into an ISUP (ISDN User Part) message of the circuit-switched network, and send it to the called terminal to set up a secondary session, and the primary session and the secondary session. Gateway to interconnect the video conferencing service providing system comprising a. The method of claim 7, wherein The exchanger of the IP network, And obtaining the network type information to which the called terminal is connected, and checking whether the called terminal is a terminal of the circuit switched network based on the obtained network type information. The method of claim 8, The exchanger of the IP network, And obtaining network type information included in the obtained location information by obtaining location information of the called terminal. The method of claim 7, wherein Further comprising: a provider management server for storing network type information of other operators, The exchanger of the IP network checks whether the connection network of the called terminal is another operator's network, and if the operator's network is another operator's network, checks whether the other operator's network is a circuit switched network from the operator management server. 11. The method of claim 10, The exchanger of the IP network, And a network type information corresponding to the identification information by transmitting identification information of the called exchange to the operator management server. delete

Images