JP2008005077A - VoIP SYSTEM, GATEWAY DEVICE, CALL AND TELEPHONE CALL HOLDING/RECOVERY PROCESSING METHOD IN MAIN SERVER FAULT TIME USED THEREFOR - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a VoIP (Voice over Internet Protocol) system by which a gateway device can start communicating with a backup server while the device holds a telephone call. <P>SOLUTION: If a communication fault occurs between a main server and a VoIP gateway device 1, the VoIP gateway device 1 starts processing for backup communication with the backup server 3. At this time, a telephone call via the VoIP gateway device 1 is continuously held. When communication between the VoIP gateway device 1 and backup server 3 is established, a state b2 of respective channels held by the VoIP gateway device 1 is reported to the backup server 3. The backup server 3 performs subsequent call establishing/clearing-out processing based upon the call state information of the respective channels reported from the VoIP gateway device 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a VoIP system, a gateway device, and a call holding / restoring method when a main server used in the VoIP system fails, and more particularly, to a call holding / restoring process when a main server fails in a VoIP (Voice over Internet Protocol) gateway device.

  In a VoIP system, a gateway device receives an instruction from a main server that controls establishment and disconnection of a call for voice communication, and provides a voice communication service by connecting an IP (Internet Protocol) network and a circuit switching network. ing. The gateway device accommodates a plurality of channels in one device for one circuit switching network.

  In the VoIP server system, it is expected that communication between the main server and the gateway device is disconnected due to a system failure of the main server, a router that relays between the central site and the remote site, or a network failure.

  To deal with this problem, a method may be considered in which a backup server is installed at the remote site, rather than all gateway devices including the remote site communicating with the unique main server at the central site.

  When the gateway device at the remote site cannot communicate with the main server due to a network failure or the like, a system that avoids a call failure due to a long-term system trouble by resuming communication with the backup server is also considered (for example, patents) Reference 1).

  Also, in a device that controls multiple channels with a single gateway device, for some failures or failures in the device, without forcibly disconnecting calls during voice communication on channels that do not affect the failure A gateway device for relief is also conceivable (see, for example, Patent Document 2).

JP 2005-006121 A JP 2005-236645 A

  In the above-described conventional VoIP system, the gateway device performs processing according to the instruction of the main server, and the main server and the gateway device due to the system failure of the main server, the failure of the router that relays between the central site and the remote site, or the network failure. It is expected that the communication with will be disconnected. However, the conventional VoIP system does not have a function for holding a call with respect to a call in progress in the above state.

  In the conventional VoIP system, in order to avoid intermittent communication disconnection with the main server, a system for realizing voice service of the gateway device by resuming communication with the backup server has been devised. There is no function for resuming communication with the backup server while maintaining the channel usage state of the gateway device.

  In the technology described in Patent Document 1, since the backup server has the same function as the main server, all call states can be newly generated by starting new communication from the gateway device to the backup server. Become.

  However, in the technique described in Patent Document 1 described above, there is no means for notifying the backup server of the communication state via the gateway device, and in the event of a sudden system down of the main server, the state in the main server is used. It is impossible to continue a call in use at the gateway device.

  In the technique described in Patent Document 2, when a failure occurs in communication with the main server in the VoIP processing unit of the gateway device, all the channels held by the gateway device are in voice communication. It will be forcibly disconnected. For this reason, the technique described in Patent Document 2 has a problem that the voice communication service cannot be continued for all calls during a call even when only a part of the processing is affected.

  Therefore, the object of the present invention is to solve the above-mentioned problems and to start communication with the backup server in a state in which the gateway device holds the call, the VoIP system, the gateway device, and the main server used for them when a failure occurs. It is to provide a call holding / recovery processing method.

The VoIP system according to the present invention receives an instruction from either a main server that controls establishment and disconnection of a call for voice communication and a backup server that backs up the main server, and is connected to an IP (Internet Protocol) network and a line. A VoIP (Voice over Internet Protocol) system including a gateway device that connects a switching network and provides a voice communication service to each terminal,
The gateway device maintains a current call state of the own device when communication with the main server is disconnected, and a call control connection process to the backup server while maintaining the current call state of the own device And a means for notifying the backup server of channel use information held in the own apparatus after the call control connection process with the backup server is started.

A gateway device according to the present invention receives an instruction from either a main server that controls establishment and disconnection of a call for voice communication and a backup server that backs up the main server, and is connected to an IP (Internet Protocol) network and a line. A gateway device for connecting a switching network and providing a voice communication service to each terminal,
Means for maintaining the current call state of the own device when communication with the main server is disconnected; and means for performing call control connection processing to the backup server while maintaining the current call state of the own device; And a means for notifying the backup server of channel use information held by the own apparatus after starting the call control connection process with the backup server.

According to the present invention, there is provided a call holding / restoring method in the event of a failure of a main server in response to an instruction from one of a main server that controls call establishment and disconnection for voice communication and a backup server that backs up the main server. Call retention / recovery processing method in case of failure of main server used in VoIP (Voice over Internet Protocol) system including gateway device for connecting voice network service to each terminal by connecting IP (Internet Protocol) network and circuit switching network Because
When the gateway device is disconnected from the main server, a process for maintaining the current call state of the own device and a call control connection process to the backup server while maintaining the current call state of the own device And a process of notifying the backup server of channel use information held by the own apparatus after starting the call control connection process with the backup server.

  That is, the VoIP (Voice over Internet Protocol) system of the present invention is used between a gateway device and a main server or a backup server during a call with a telephone terminal on the ISDN (Integrated Services Digital Network) network side via the gateway device. Even when communication is interrupted, the voice communication service can be maintained.

  In the VoIP system of the present invention, when the gateway device is disconnected from the main server or the backup server, it is possible to determine the end of the telephone terminal currently talking on the own device.

  In the VoIP system of the present invention, when communication with the main server is disconnected in the gateway device, the call control connection process to the backup server is performed while maintaining the current call state of the gateway device.

  Furthermore, in the VoIP system of the present invention, after the gateway device starts the call control connection process with the backup server, it notifies the backup server of the channel usage information held by the gateway device, so that the latest information held by the gateway device is stored. Communication with the backup server can be started in the call state.

In the VoIP system of the present invention, the gateway device is not an instruction of the main server, but as a determination condition for terminating the call,
-When the gateway device becomes unable to receive a data transfer packet [RTP (Real Time Transport Protocol) packet] from an IP (Internet Protocol) network terminal for a certain period of time-The gateway device receives a TTC (Telecommunication Technology Committee) standard JT -Q. When the Layer 3 disconnection processing message conforming to 931 is received, the case can be realized in three cases: when the gateway apparatus detects that the line link state of Layer 2 or lower of the ISDN network is down.

  By adopting the above-described configuration and operation, the present invention provides an effect that communication with the backup server can be started in a state where the gateway device holds a call.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of a VoIP (Voice over Internet Protocol) system according to an embodiment of the present invention. In FIG. 1, a VoIP system according to an embodiment of the present invention is a voice communication system including a VoIP gateway device 1.

  A VoIP system according to an embodiment of the present invention includes a VoIP gateway device 1, a main server 2 that manages the VoIP system, a backup server 3 installed at a remote site, a router 4, and an IP (Internet Protocol) network 100 side. A telephone 5 that is a terminal and a telephone 6 that is a terminal on the ISDN (Integrated Services Digital Network) network 200 side are provided.

  The telephone 6 and the VoIP gateway device 1 are connected via the ISDN network 200, and the VoIP gateway device 1, the main server 2 and the backup server 3 are connected via the IP network 100. Further, the VoIP gateway device 1 and the telephone 5 are connected via the IP network 100.

  FIG. 2 is a block diagram showing a configuration example of the VoIP gateway device 1 of FIG. In FIG. 2, the VoIP gateway device 1 accommodates a plurality of voice channels, a VoIP interface processing unit 11 for processing a control instruction command from the main server 2 and the backup server 3, voice data and IP of the ISDN network 200. It is composed of a VoIP media processing unit 12 that mutually converts voice packets of the network 100 and an ISDN interface processing unit 13 that terminates an interface of the ISDN network 200.

  The VoIP interface processing unit 11 is a channel corresponding to a state monitoring (health check) process between the main server 2 and the backup server 3 and the gateway device 1 and a call start and call disconnection instruction from the main server 2 and the backup server 3. The ISDN network 200 and the IP network 100 are connected.

  The VoIP media processing unit 12 is equipped with a DSP (Digital Signal Processor), and instructs the main server 2 or the backup server 3 to transmit voice data of the ISDN network 200 and voice packets of the IP network 100 notified from the ISDN interface processing unit 13. Mutual conversion processing is performed in accordance with the voice encoding method.

  The ISDN interface processing unit 13 is a TTC (Telecommunications Technology Committee) standard JT-Q. The data of the ISDN network 200 is terminated according to the line control system 931. Also, the ISDN interface processing unit 13 monitors the circuit switching messages of each layer, monitors the link state of the VoIP gateway device 1 on the ISDN network 100 side, and manages the call states of all channels accommodated by the VoIP gateway device 1. . Further, the ISDN interface processing unit 13 notifies the VoIP media processing unit 12 of the voice data received from the telephone 6 via the ISDN network 200.

  FIG. 3 is a diagram showing reconnection processing from the main server 2 to the backup server 3 in FIG. 1, and FIG. 4 is a sequence chart showing reconnection processing from the main server 2 to the backup server 3 in FIG. The operation of the VoIP system according to an embodiment of the present invention will be described with reference to FIGS.

  First, an operation process of the VoIP gateway device 1 when the communication between the main server 2 and the VoIP gateway device 1 is continuously disconnected will be described.

  The VoIP interface processing unit 11 has a function of monitoring a health check between the main server 2 of the central site 101 and the VoIP gateway device 1. In this health check function, when the VoIP gateway device 1 determines that a health check timeout has occurred, the VoIP gateway device 1 starts communication with the backup server 3 of the remote site 102 designated in advance. The VoIP interface processing unit 11 can relieve communication between the main server 2 and the VoIP gateway device 1 from intermittent communication failures by switching communication with a plurality of servers.

  Even when the health check timeout has not occurred, the gateway device 1 starts communication with the backup server 3 designated in advance when the main server 2 forcibly instructs it.

  In the VoIP media processing unit 12, a call disconnect instruction from the main server 2 is notified via the VoIP interface processing unit 11 in a normal processing state. When there is no instruction from the main server 2 due to a failure of the main server 2 or the like, the VoIP media processing unit 12 holds a call through the VoIP gateway device 1.

  When the opposite device on the IP network 100 side disconnects the call, the VoIP media processing unit 12 determines the end of the call and executes the disconnection process in the VoIP gateway device 1. This end-of-call determination is made when a data transfer packet [RTP (Real Time Transport Protocol) packet] cannot be received from the opposite device terminal of the IP network 100 for a certain period of time.

  In the ISDN interface processing unit 13, similarly to the VoIP media processing unit 12, when there is no instruction from the main server 2 due to a failure of the main server 2, the ISDN network 200 is used to hold a call through the VoIP gateway device 1. The VoIP media processing unit 12 is notified of the voice data received from the telephone set 6 via.

  Further, when a disconnection instruction is notified from the ISDN network 200 side, the ISDN interface processing unit 13 determines the end of the call and executes the disconnection process in the VoIP gateway device 1. As the determination of the end story, TTC standard JT-Q. Assume that a Layer 3 line disconnection message is received and a Layer 2 link disconnection is detected in accordance with the 931 line control method. The line message that is determined to be the end of speech is three messages “DISCONNECT”, “RELEASE”, and “RELEASE COMP”.

  In a state where the VoIP gateway device 1 holds a call between the telephone 6 and the telephone 5 which are terminals of the ISDN network 200 (call state b in FIG. 3) (a1 in FIG. 4), the main server 2 and the VoIP gateway device 1 When a communication failure (failure occurrence a in FIG. 3) occurs between the VoIP gateway device 1 (a2 in FIG. 4), the VoIP gateway device 1 starts backup communication processing to the backup server 3 (a4, a6 in FIG. 4).

At this time, the call through the VoIP gateway device 1 continues to be held (a5 in FIG. 4). As a condition for disconnecting a call that was in progress before the communication failure occurred,
When the data transfer packet (RTP packet) from the telephone 5, which is a terminal on the IP network 100 side, is unreceivable for a certain period of time. The VoIP gateway device 1 is connected to the TTC standard JT-Q. When the Layer 3 disconnection processing message conforming to 931 is received, the VoIP gateway apparatus 1 detects that the line link status of the Layer 2 or lower of the ISDN network 200 is down.

  When the communication between the VoIP gateway device 1 and the backup server 3 is established, the status b2 of each channel held by the VoIP gateway device 1 is notified to the backup server 3 (a7, a8 in FIG. 4). Based on the call status information b3 of each channel notified from the VoIP gateway device 1, the backup server 3 performs subsequent call establishment and call termination processing (a9 in FIG. 4).

  The call status information notified from the VoIP gateway device 1 to the backup server 3 includes an extension terminal number (IP address and registration number to the server system) that can uniquely determine the opposite device terminal on the IP network 100 side, an ISDN network The call number of the 200 telephone is used. In addition, after establishing communication between the backup server 3 and the VoIP gateway device 1, the VoIP gateway device 1 can perform a call service process in accordance with an instruction from the backup server 3.

  In this way, in this embodiment, the VoIP gateway device 1 can maintain a call by monitoring both states of the IP network 100 side and the ISDN network 200 side, so the main server 2 and the VoIP gateway device 1 can be maintained. Even when a communication failure occurs between the VoIP gateway device 1 and the VoIP gateway device 1, the call can be held.

  Further, in this embodiment, when the communication with the backup server 3 is switched, the backup server 3 manages the opposite device information to which the VoIP gateway device 1 is connected from the VpIP gateway device 1 to the backup server 3. Since the information to be updated can be updated, communication with the backup server 3 can be started in a state where the VoIP gateway device 1 holds the call.

  For the telephone terminal on the IP network 100 side, the data transfer packet (RTP packet) on the IP network 100 side is monitored to maintain the call even when the communication between the main server 2 and the VoIP gateway device 1 is disconnected. It can be carried out.

  The above embodiment is applied to the case where the telephone set 6 and the VoIP gateway apparatus 1 are connected via the ISDN network 200. However, the telephone set 6 and the VoIP gateway apparatus 1 are connected to the circuit switching network in the same manner as the ISDN network 200. The present invention can also be applied to a case of being connected through a PSTN (Public Switched Telephony Network) network.

It is a block diagram which shows the structural example of the VoIP system by one Example of this invention. It is a block diagram which shows the structural example of the VoIP gateway apparatus of FIG. It is a figure which shows the reconnection process from the main server of FIG. 1 to a backup server. It is a sequence chart which shows the reconnection process from the main server of FIG. 1 to a backup server.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 VoIP gateway apparatus 2 Main server 3 Backup server 4 Router 5, 6 Telephone 11 VoIP interface processing part 12 VoIP media processing part 13 ISDN interface processing part 100 IP network 101 Central site 102 Remote site 200 ISDN network

Claims (13)

In response to an instruction from one of a main server that controls call establishment and disconnection for voice communication and a backup server that backs up the main server, an IP (Internet Protocol) network and a circuit switching network are connected. A VoIP (Voice over Internet Protocol) system including a gateway device that provides a voice communication service to each terminal,
The gateway device maintains a current call state of the own device when communication with the main server is disconnected, and a call control connection process to the backup server while maintaining the current call state of the own device And a means for notifying the backup server of channel use information held by the own apparatus after the call control connection process with the backup server is started.   2. The VoIP system according to claim 1, wherein the gateway device includes means for determining whether or not to terminate the currently talking terminal when communication with the main server is disconnected.   3. The VoIP system according to claim 1, wherein the means for maintaining the call state maintains the call state by monitoring states of the IP network side and the circuit switching network.   When the gateway apparatus receives a data transfer packet from a terminal on the IP network side for a certain period of time, or receives a layer 3 disconnection processing message from the circuit switched network, the gateway apparatus performs layer 2 or lower of the circuit switched network. 4. The VoIP system according to claim 3, wherein it is determined that the call of the currently active terminal is terminated in any of the cases where it is detected that the line link state of the terminal is down. In response to an instruction from one of a main server that controls call establishment and disconnection for voice communication and a backup server that backs up the main server, an IP (Internet Protocol) network and a circuit switching network are connected. A gateway device that provides voice communication services to each terminal,
Means for maintaining the current call state of the own device when communication with the main server is disconnected; and means for performing call control connection processing to the backup server while maintaining the current call state of the own device; A gateway device comprising: means for notifying the backup server of channel use information held by the own device after the call control connection process with the backup server is started.   6. The gateway device according to claim 5, further comprising means for determining whether or not to terminate the terminal currently in a call when communication with the main server is disconnected.   7. The gateway apparatus according to claim 5, wherein the means for maintaining the call state maintains the call state by monitoring the states of the IP network side and the circuit switching network.   When a data transfer packet from a terminal on the IP network side cannot be received for a certain period of time, or when a layer 3 disconnection processing message is received from the circuit switched network, the circuit link status below the layer 2 of the circuit switched network is 8. The gateway apparatus according to claim 7, wherein it is determined that the call of the terminal that is currently in a call is ended in any case where it is detected that the terminal is down.   8. The gateway device according to claim 5, wherein the gateway device constitutes a VoIP (Voice over Internet Protocol) system. In response to an instruction from one of a main server that controls call establishment and disconnection for voice communication and a backup server that backs up the main server, an IP (Internet Protocol) network and a circuit switching network are connected. A method for maintaining and restoring a call when a main server fails in a VoIP (Voice over Internet Protocol) system including a gateway device that provides a voice communication service to each terminal,
When the gateway device is disconnected from the main server, a process for maintaining the current call state of the own device and a call control connection process to the backup server while maintaining the current call state of the own device And a process for notifying the backup server of channel use information held by the own apparatus after the call control connection process with the backup server is started. Method.   The call holding / recovering according to claim 10, wherein the gateway device executes a process of determining whether or not to end a call of a currently busy terminal when communication with the main server is disconnected. Processing method.   12. The call holding / recovering according to claim 10 or 11, wherein, in the process of maintaining the call state, the call state is maintained by monitoring states of the IP network side and the circuit switching network. Processing method.   When the gateway device cannot receive a data transfer packet from a terminal on the IP network side for a certain period of time, or receives a layer 3 disconnection processing message from the circuit switched network, 13. The call holding / restoring processing method according to claim 12, further comprising: determining that the call of the terminal that is currently calling is terminated in any case where it is detected that the line link state of the terminal is down.

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