KR100673174B1 - System and method for videotelephony call interworking in different network - Google Patents

Abstract

Disclosed are a video telephone call processing system and a method for heterogeneous networks capable of interworking a packet network based video telephone and a circuit network based video telephone. Accordingly, the present invention is based on the Interworking Media Gateway (IMG) that performs bearer conversion and IP Multimedia Subscriber Register (IMSR) integrating H.323 videophone subscriber DB and 3G-324M videophone subscriber DB. Performs videophone call processing.

Video call, packet network, circuit network, subscriber DB, IMG

Description

Video telephony call processing system in heterogeneous network and its method {SYSTEM AND METHOD FOR VIDEOTELEPHONY CALL INTERWORKING IN DIFFERENT NETWORK}

1 is a diagram showing a video telephone call processing system in a heterogeneous network according to an embodiment of the present invention.

2A to 2C are flowcharts illustrating a video telephone call processing method from a packet network to a circuit network according to an embodiment of the present invention.

3A to 3B are flowcharts illustrating a video telephone call processing method from a circuit network to a packet network according to an embodiment of the present invention.

* Explanation of Codes on Major Parts of Drawings *

110: H.323 videophone

120: Gate Keeper

130: Interworking Medium Gateway (IMG)

140: IP Multimedia Subscriber Register (IMSR)

150: Dual-stack Home Location Register (DHLR)

160: MSCg (MSC gateway)

170, 190: MSC

180: 3G-324M video phone

The present invention relates to a video telephony call processing system and a method thereof, and more particularly, to a video telephony call processing system and a method for heterogeneous networks interworking a video network based on a packet network and a video network based on a circuit network.

Wireless mobile communication ^{technology, 3GPP (3 rd Generation Partnership Projects} ) haewatgo development as GSM, GPRS, WCDMA networks standardized by the international standardization ^{conference, 3GPP2 (3 rd Generation Partnership Projects} 2) normalized by the International Standardization Meeting IS-95A, IS95 -B, CDMA20001x, CDMA1x-EVDO.

Among these wireless mobile communication technologies, in the case of the IMT-2000 network, the synchronous IMT-2000 is called CDMA2000 1x-EVDO, and the asynchronous IMT-2000 is called WCDMA.

On the other hand, for video telephony service, WCDMA network is provided based on wired circuit network, and part of ITU-T H.324 protocol standard is changed to 3GPP standardization organization for wireless circuit network and standardized to 3G-324M protocol standard. On the other hand, in the CDMA2000 1x-EVDO network, the ITU-T H.323 protocol standard used in the wired packet network is used for the wireless packet network without a separate standard specification in the wireless network.

Therefore, for the video telephony interworking in the IMT-2000 network (WCDMA network and CDMA20001x-EVDO network), in particular, the need for a specific call processing process that can provide a video telephony service between the packet network and the circuit network is increased.

The present invention has been drawn to solve the above problems, an object of the present invention is a video telephone call processing system and method in a heterogeneous network capable of interworking a packet network based video telephone and a circuit network based video telephone To provide.

In order to achieve the above object, a call processing system between a packet network based video telephone and a circuit network based video telephone according to the present invention comprises a video telephone call processing and subscriber DB for providing a video telephone service in the packet network. A gate keeper (GK) for providing; An Interworking Media Gateway (IMG) for performing protocol conversion between the packet network and the circuit network; An IP Multimedia Subscriber Register (IMSR), which is an integrated subscriber DB of the packet network subscriber and the circuit network subscriber; Dual-stack Home Location Register (DHLR) which is a subscriber DB of the circuit network; An MSCg serving as a gateway for routing between exchanges in the circuit network; And MSC which is an exchanger of the circuit network.

On the other hand, the video phone call processing method in a heterogeneous network for the video phone call connection from the packet network-based video phone to the circuit network-based video phone according to the present invention, (a) querying the incoming video phone in the packet network ; (b) performing a call from the packet network to a circuit network if there is no incoming video call in the packet network as a result of the inquiry; (c) querying an incoming video call in the circuit network; (d) if the incoming result is an incoming video call in the circuit network, the incoming video call performing an incoming response process from the circuit network to the packet network; And (e) performing a video telephone call connection and disconnection between the packet network based video telephone and the circuit network based video telephone.

In addition, a video telephone call processing method in a heterogeneous network for connecting a video telephone call from a circuit network based video telephone to a packet network based video telephone according to the present invention includes: (a) querying an incoming video telephone in the circuit network; step; (b) if there is no incoming video call in the circuit network as a result of the inquiry, performing broadcasting for the incoming video call over the packet network; (c) the incoming video call in the packet network detected as a result of the broadcasting, performing the incoming call; (d) the incoming video call performing an incoming response process from the packet network to the circuit network; And (e) performing a video telephone call connection and disconnection between the circuit network based video telephone and the packet network based video telephone.

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

The present invention is an IMMG (IP Multimedia Subscriber Register) incorporating an H.323 videophone subscriber DB and a 3G-324M videophone subscriber DB (HSS (Home Subscriber Server) in the international standard) and an IMG that performs bearer conversion. Based on the Interworking Media Gateway, a video phone call processing process in a heterogeneous network will be described in more detail.

As an example of the heterogeneous example, a CDMA1x-EVDO network (a packet network interoperating with an H.323 videophone) and a WCDMA network (a circuit network interoperating with a 3G-324M videophone) will be described.

1 is a diagram showing a video telephone call processing system in a heterogeneous network according to an embodiment of the present invention.

As shown in Fig. 1, the system is a system for call processing between a packet network (H.323 video phone 110 is connected) and a circuit network (3G-324M video phone 180 is connected). A gatekeeper (Gate Keeper, GK) 120 for providing a videophone call processing and subscriber DB for providing a videophone service in a packet network; An IMG (Interworking Media Gateway, 130) for performing protocol conversion between the packet network and the circuit network; An IP Multimedia Subscriber Register (IMSR) 140 which is an integrated subscriber DB of the packet network subscriber and the circuit network subscriber; A dual-stack home location register (DHLR) 150 which is a subscriber DB of the circuit network; An MSCg (MSCg) 160 serving as a gateway for routing between exchanges in the circuit network; And MSCt 170 or MSCo 190, which are exchangers in the circuit network.

Here, the GK 120 processes functions interworking with other multimedia systems in the H.323 protocol system, heterogeneous networks (circuit networks in this embodiment), call setup, protocol conversion for release, media conversion, and the like. In addition, the GK 120 communicates with the H.323 videophone 110 using H.225 (call signaling) or H.245 (control signaling) as well as providing an H.323 videophone subscriber DB. do.

In addition to the video phone subscriber DB role, the IMSR 140 plays the role of a subscriber DB for additional services such as IM, PTT, coloring, video mailbox service, and the like.

The MSCg 160 is an MSC serving as a gate of the packet network and the circuit network as an MSC gateway, and the MSCo 190 and the MSCt 170 represent an exchange in a home network and an exchange in a visited network, respectively.

Hereinafter, a video telephone call processing method in a heterogeneous network according to an embodiment of the present invention will be described with reference to the accompanying drawings.

2A to 2C are flowcharts illustrating a video telephone call processing method from a packet network to a circuit network according to an embodiment of the present invention.

1) Inquiry of incoming terminal in packet network

The H.323 video phone 110 (hereinafter referred to as a calling terminal) transmits an ARQ (Admission Request) message, which is an outgoing request message including a called number, to the GK 120 (S201).

The GK 120 searches for its subscribers in the H.323 videophone and checks its DB, and if it is not a subscriber of the H.323 videophone, the subscriber of the 3G-324M 170 (hereinafter referred to as an incoming terminal) to the IMSR 140. A message for requesting location information Cx_LIR (Location Information Request) is transmitted (S202). Here, Cx refers to Cx_interface, which is a text-based protocol mainly used in the IMSR 140 in an All IP network (IMS) network.

The IMSR 140 checks the called subscriber in its DB based on the request message from the GK 120 (ie, whether to subscribe to a video call service), and then requests subscriber information to the circuit network DHLR 150 (MAP_AnyTimeSubInterrogation). ) Send a message (S203).

DHLR 150 transmits a response message to the subscriber information request message to IMSR 140 (S204). At this time, the response message transmits the video telephone type information (eg, H.323 video telephone, SIP video telephone, 3G-324M video telephone, etc.) of the called terminal 180.

Then, the IMSR 140 transmits a Cx_LIA (Location Information Ack) message indicating that the called terminal 180 is a 3G-324M video telephone to the GK 120 (S205).

Subsequently, the GK 120 transmits a Location Request (LRQ) message requesting the location information of the called terminal 180 to the IMG 130, and the IMG 130 transmits the location to the GK 120 as a response message of the LRQ. The LCF (Location Confirm), which is a confirmation message, is transmitted (S206-S207).

Thereafter, the GK 120 transmits an ACF (Admission Confirm) message to the calling terminal 110 as an acknowledgment message for the ARQ message (S208).

Based on the above-described process, the GK 120 knows that the called terminal 180 is a 3G-324M video phone based on a circuit network.

2) Outgoing from Packet Network to Circuit Network

Thereafter, the originating terminal 110 transmits a TCP Sync control message for the purpose of synchronizing the TCP connection to the GK 120, and the GK 120 establishes a TCP connection setup message to the originating terminal 110. It transmits (S209-S210).

In addition, the calling terminal 110 transmits a setup message (H.225 call signaling setup) for setting up a call to the IMG 130 through the GK 120 (S211-S212), and the IMG 130 sends a GK. The call setup progress request (Call Proceeding) message is transmitted to the calling terminal 110 through 120 (S213-S214). At the same time, the IMG 130 transmits an IAM (TMR, USI) message, which is a pre-call setup request message, to the MSCg 160 (S215).

3) Incoming terminal in circuit network

Thereafter, the MSCg 160 transmits a MAP_SRI (UDI), which is a message for requesting location information of the called terminal 180, to the DHLR 150 (S216). At this time, MAP_SRI (Send Routing Information) is a message for requesting location information, and UDI (Unrestricted Digital Information) is a parameter representing the called terminal 180, so MAP_SRI (UDI) requests the location information of the called terminal 180. Is a message.

The DHLR 150 transmits MAP_PRN (UDI), which is a message for requesting provision of routing information of the called terminal 180, to the MSCt 170 (S217). That is, PRN (Providing Routing Number) is a routing information provision request message (SRI), MAP_PRN (UDI) is a message requesting the provision of routing information of the called terminal 180.

In response to the routing information request message for the destination terminal 180 of the DHLR 150, the MSCt 170 transmits a MAP_PRN_Ack (MSRN) message as a response message to the DHLR 150 (S218). In this case, the MSRN is a mobile station routing number and indicates routing information to the called terminal 180.

Then, the DHLR 150 transmits a MAP_SRI (UDI, MSRN) message to the MSCg 160, that is, a response message to the MAP_SRI (UDI) (S219). That is, the position information on the video call is transmitted, and the MSCg 160 transmits IAM (TMR, USI), which is a pre-call setup request message for transmitting the video call, to the MSCt 170 (S220).

Through the above-described process, the IMG acquires the location information of the called terminal 180 in the circuit network, and transmits an ISUP message to the MSCt interworking with the called terminal 180.

4) Incoming response from circuit network to packet network

Subsequently, when the MSCt 170 transmits a Setup message to the called terminal 180 (S221), the called terminal 180 passes through the MSCt 170, the MSCg 160, the IMG 130, and the GK 120. An incoming response message is transmitted to the calling terminal 110, that is, an alerting and an ACM (Address Confirm) message, which is a response message to the setup message and the ISUP message, is transmitted (S222-S226).

Then, the called terminal 180 connects to the MSCt 170 through the wireless network, and then transmits an ANM (Answer Message) for requesting connection to the IMG 130 via the MSCg 160 (S222-). S229), and performs the H.245 negotiation for the call connection with the IMG (130) (S230).

That is, the called terminal 180 and the IMG 130 are composed of Master / Slave Determination (MSD), Exchange Terminal Capabilities (ETC), Open Logical Channel (OLC), and Multiplex Table. Negotiate information for connection by video call, such as Signaling (Multiplex Table Signaling, MES). In particular, in the case of MES, since the called terminal 180 is a circuit network based video telephone, an audio / video signal is multiplexed and transmitted. Therefore, the IMG 130 is important to negotiate the MES.

Subsequently, the IMG 130 makes a call connection request to the calling terminal 110 via the GK 120 (S230-S232).

5) Video call call connection and disconnection

As described above, when a call connection between the called terminal 180 and the calling terminal 110 is completed, a video call path for a video call is formed.

That is, the IMG 130 connects the calling terminal 110 with the audio / video video call path based on the RTP / UDP / IP protocol, and the calling terminal 180 is based on the H.223 audio. By connecting the video / video channel, the calling terminal 110 and the called terminal 180 are connected to the video call through the IMG (130).

Thereafter, when the video call is completed between the video phones (for example, when the calling terminal 110 ends the video call), the call release process is performed.

That is, in order to release the session between the calling terminal 110 and the IMG 130, after exchanging a request message and a response message for the end session, the calling terminal 110 through the GK 120 IMG (130) RLC (Release Complete), which is a release complete message, is transmitted (S233-S235).

Subsequently, the IMG 130 transmits a session release request message REL (Release) to the MSCt 170 via the MSCg 160 (S236-S237). The MSCt 170 terminates the session with the terminating terminal 180 and transmits an RLC, which is a release completion message, to the IMG 130 via the MSCg 160 (S238-S240).

Thereafter, the originating terminal 110 transmits a DRQ (Disengage Request), which is a call termination message, to the GK 120, and the GK 120 transmits a DCF (Disengage Confirm) to the originating terminal 110 as a response message. , The call connection is released (S241-S242).

3A to 3B are flowcharts illustrating a video telephone call processing method from a circuit network to a packet network according to an embodiment of the present invention.

1) Search incoming terminal in circuit network

When the 3G-324M video telephone 180 (hereinafter referred to as a calling terminal) dials the called number, a call setup message is transmitted to the MSCo 190 (S301).

The MSCo 190 transmits MAP_SRI (UDI), which is a message for requesting location information of the terminal corresponding to the called number, to DHLR (S302). In addition, the DHLR 150 transmits to the MSCo 190 a MAP_SRI message indicating that the terminal corresponding to the called number is an H.323 subscriber, not a circuit based terminal (S303). Then, the MSCo 190 transmits an IAM (TMR, USI) message, which is a pre-call setup request message, to the IMG 130 via the MSCg 160 (S304).

The MSCo 190 interworking with the calling terminal 180 through the above-described process knows that the called terminal 110 does not exist in the circuit network, and transmits an ISUP message including the called number to the IMG 130.

2) Broadcasting in Packet Network

Accordingly, the IMG 130 broadcasts an LRQ (Location Request) message requesting location information of the H.323 videophone 110 (hereinafter referred to as a called terminal) corresponding to the called number to at least one GK 120. Then, the corresponding GK 120 interworking with the called terminal 110 transmits a location confirmation (LCF) to the IMG 130 as a response message of the LRQ (S305-S306).

3) Incoming in packet network

Subsequently, when the IMG 130 transmits a setup message (H.225 call signaling setup) for setting up a call with the called terminal 110 to the GK 120, the GK 120 connects to the called terminal 110 with a TCP connection. A TCP Sync control message is transmitted for the purpose of synchronizing the data, and the called terminal 110 transmits a TCP connection setup message for establishing a TCP connection to the GK 120 (S307-S310).

Subsequently, when the called terminal 110 transmits an ARQ (Admission Request) message, which is a call setup request message, to the GK 120, the GK 120 sends an ACF (Admission Confirm), which is a call setup response message, to the called terminal 110. Transmit (S311-S312).

4) Incoming response from packet network to circuit network

The incoming terminal 110 transmits a call setup progress message to the IMG 130 through the GK 120 and then responds to the setup message through the GK 120 and the IMG 130. The IMG 130 transmits an Alerting message, which is a message, and sends an ACM (Address Confirm), an Alert message, which is a response message to the ISUP message, to the calling terminal 180 through the MSCg 160 and the MSCo 190 ( S313-S319).

In addition, when the called terminal 110 transmits a call connection request message (Connect) to the IMG 130 via the GK 120, the IMG 130 sends an ANM (Answer Message) via the MSCo (190). 180) (S320-S324).

The IMG 130 performs H.245 negotiation with the calling terminal 180 (S325). That is, the originating terminal 180 and the IMG 130 are master / slave determination (MSD), exchange terminal capabilities (ETC), open logical channel (OLC), multiplex table Negotiate information for connection by video call, such as Signaling (Multiplex Table Signaling, MES).

5) Connect and disconnect video call

Thereafter, the IMG 130 connects the incoming terminal 110 with an audio / video video call path based on the RTP / UDP / IP protocol, and the calling terminal 180 based on H.223 audio. By connecting the video / video call path, the calling terminal 180 and the called terminal 110 establish a video call path through the IMG 130.

On the other hand, when the video call is completed between the video phones (for example, when the calling terminal 180 ends the video call), the call release process is performed.

That is, when the calling terminal 180 transmits a call termination message to the MSCo 190, the MSCo 190 transmits a release request message REL (Release) to the IMG 130 (S326-S327). Then, in order to release the session between the IMG 130 and the called terminal 110, after exchanging a request message and a response message for the End Session, the IMG 130 through the GK 120, the called terminal 110 RLC (Release Complete), which is a release complete message, is transmitted (S328-S330). In addition, the IMG 130 transmits a release complete (RLC) to the MSCo 190 (S331).

Thereafter, the terminating terminal 110 transmits a DRQ (Disengage Request), which is a call termination message, to the GK 120, and the GK 120 transmits a DCF (Disengage Confirm) to the terminating terminal 110 as a response message. , The call connection is released (S332-S333).

While the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will recognize that various modifications or changes can be made without departing from the spirit and scope of the invention.

As described above, according to the present invention, it is possible to perform video telephony even in heterogeneous networks based on IMSR and bearer conversion integrating H.323 video telephony subscriber DB and 3G-324M video telephony subscriber DB. .

Claims (17)

A system for call processing between packet network based video telephony and circuit network based video telephony, A gate keeper (GK) for providing a videophone call processing and a subscriber DB for providing a videophone service in the packet network; An Interworking Media Gateway (IMG) for performing protocol conversion between the packet network and the circuit network; An IP Multimedia Subscriber Register (IMSR), which is an integrated subscriber DB of the packet network subscriber and the circuit network subscriber; Dual-stack Home Location Register (DHLR) which is a subscriber DB of the circuit network; An MSCg serving as a gateway for routing between exchanges in the circuit network; And MSC, which is an exchanger of the circuit network, The GK obtains subscriber information of an incoming videophone by inquiring the DHLR through the IMSR, and the IMG performs H.245 negotiation on an incoming videophone and a call connection. Call processing system. The system of claim 1, wherein the IMSR performs a subscriber DB role for a video telephone supplementary service. The system of claim 2, wherein the additional service comprises at least one of an IM service, a PTT service, a presence service, a coloring service, and a video mailbox service. A video telephone call processing method in a heterogeneous network for connecting a video telephone call from a packet network based video telephone to a circuit network based video telephone, (a) querying an incoming video call in a packet network; (b) performing a call from the packet network to the circuit network if there is no incoming video call in the packet network as a result of the inquiry in step (a); (c) querying an incoming video call in the circuit network; (d) if the incoming video call exists in the circuit network as a result of the inquiry in step (c), the incoming video call performing an incoming response process from the circuit network to the packet network; And (e) performing video telephone call connection and disconnection between the packet network based video telephone and the circuit network based video telephone. In the step (a), the originating video call transmits an ARQ (Admission Request) message to the GK, the GK obtaining subscriber information of the incoming video call through IMSR and DHLR, and the GK to the outgoing video call. Sending a call setup response message; In step (d), the MSC transmits a setup message to the incoming videophone, and the incoming videophone transmits an incoming response message to the outgoing videophone via the MSC, MSCg, IMG, and GK. Performing a H.245 negotiation on a call connection with the IMG after the video call transmits a call connection request message to the IMG, and the IMG transmits a call connection request message to the outgoing video call via the GK. And a video telephone call processing method in heterogeneous networks. The method of claim 4, wherein step (b) comprises: (b-1) the sending video call sending a TCP synchronous control message to the GK for a TCP connection, and the GK sending a TCP connection setting message to the calling video call; (b-2) the outgoing video call transmitting a setup message for call setup to the IMG via the GK; And (b-3) the IMG transmitting a pre-call setup request message to MSCg. 6. The video telephone call processing in heterogeneous networks according to claim 5, wherein the step (b-3) further comprises the step of the IMG transmitting a call setup progress request message to the outgoing video telephone via GK. Way. delete 5. The method of claim 4, wherein the subscriber information includes subscriber location information of the incoming video phone. The method of claim 4 or 5, wherein the step (c), (c-1) the MSCg acquiring the location information of the incoming video call through DHLR and the MSC; And (c-2) the MSCg transmitting a pre-call setup request message to the MSC for transmitting the videophone call based on the obtained location information of the incoming videophone. How to handle phone calls. delete The method of claim 4 or 5, wherein step (e) (e-1) The IMG connects an audio / video video call path based on the RTP / UDP / IP protocol with an outgoing video call, and the audio / video picture based on H.223 with the incoming video call. Connecting a channel; And (e-2) performing a call release between the outgoing video call and the incoming video call. A video telephone call processing method in a heterogeneous network for connecting a video telephone call from a circuit network based video telephone to a packet network based video telephone, (a) querying an incoming video call in the circuit network; (b) if there is no incoming video call in the circuit network as a result of the inquiry, performing broadcasting for the incoming video call over the packet network; (c) the incoming video call in the packet network detected as a result of the broadcasting, performing the incoming call; (d) the incoming video call performing an incoming response process from the packet network to the circuit network; And (e) performing a video telephone call connection and disconnection between the circuit network based video telephone and the packet network based video telephone, In step (b), IMG broadcasts a Location Request (LRQ) message requesting location information of an incoming video call to at least one GK, and a corresponding GK interworking with the incoming video call is an LCF (Location) as a response message of the LRQ to the IMG. Confirm) A video telephone call processing method in a heterogeneous network comprising the step of transmitting a message. delete The method of claim 12, wherein step (a) comprises: (a-1) when the outgoing video call dials a predetermined called number, a call setup message is transmitted to the MSC; (a-2) the MSC transmitting a message requesting the location information of the incoming video call corresponding to the called number to DHLR; (a-3) the DHLR transmitting a message indicating to the MSC that the incoming video call corresponding to the called number is not a circuit network based video telephone subscriber but a packet network based video telephone subscriber; And (a-4) The MSC transmits a pre-call setup request message to the IMG via the MSCg. The method of claim 12, wherein step (c) comprises: (c-1) When the IMG sends a setup message for setting up a call with the incoming video phone to the GK, the GK sends a TCP Sync control message for the purpose of synchronizing a TCP connection to the incoming video phone. Transmitting, by the incoming videophone, a TCP connection setup message for establishing a TCP connection to the GK; And (c-2) when the incoming video call transmits an ARQ (Admission Request) message to the GK, the GK transmits an Admission Confirm (ACF) message to the incoming video call. Videophone call processing in. The method of claim 12, wherein step (d) (d-1) transmitting, by the incoming videophone, an alerting message which is a response message to a call setup progress request message and a setup message to the IMG through the GK; (d-2) the IMG sending an ACM (Address Confirm) message, which is a response message for the ISUP message, to the MSC via the MSCg; (d-3) transmitting, by the MSC, an Alert message which is a response message to a call setup message to an outgoing video telephone; (d-3) the incoming video call sending a call connection request message to the outgoing video call via the GK, IMG, and MSC; And (d-4) the IMG performing a H.245 negotiation with the outgoing video call. The method of claim 12, wherein step (e) (e-1) The IMG connects an audio / video video call path based on the RTP / UDP / IP protocol with an outgoing video call, and the audio / video picture based on H.223 with the incoming video call. Connecting a channel; And (e-2) performing a call release between the outgoing video call and the incoming video call.

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