JP2010021671A - Media gateway apparatus, communication system, and redundancy method used itherein - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a media gateway apparatus capable of minimizing cost increase and improving reliability just like a duplex configuration. <P>SOLUTION: The media gateway apparatus (1) has: active system and standby system VoIP control means (VoIP control parts 14-17) for at least making sound data into RTP packets and performing medium conversion to the sound data of the RTP packet; and the call control management means of the duplex configuration (call control management parts 11, 12) for setting information needed for VoIP session establishment to the VoIP control means. The media gateway apparatus sets the information set to the VoIP control means to the standby system VoIP control means by the call control management means when a fault is caused in the active system VoIP control means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a media gateway device, a communication system, and a redundancy method used therefor, and more particularly to a media gateway device (MGW: Media Gateway) that connects an existing circuit switching network and an IP (Internet Protocol) network.

  A media gateway apparatus redundancy method related to the present invention will be described with reference to FIGS. 7 and 8, the media gateway device 4 includes a VoIP (Voice over Internet Protocol) control unit (# 1 to # 3) 41 to 43, a VoIP control unit (standby) 44, and a line ITF (Interface) unit. (# 0, # 1) 45, 46.

  The VoIP control units (# 1 to # 3) 41 to 43 and the VoIP control unit (reserved) 44 are Megaco (Megaco) termination function, call control management function, VoIP function [RTP (Real-time Transport Protocol) packet of voice data. , Media conversion from RTP to audio data, codec conversion, echo canceller, etc.]. The VoIP control units (# 1 to # 3) 41 to 43 operate as active systems, the VoIP control unit (reserved) 44 operates as a standby system, and the line ITF units (# 0, # 1) 45 and 46 operate as circuit switched networks ( Interface function (not shown).

  The VoIP control unit (standby) 44 has context information of all the active VoIP control units (# 1 to # 3) 41 to 43, and from the MGC (Media Gateway Control) 5 to the active VoIP control unit (# 1). ) 41, the context information table of the VoIP control unit (standby) 44 is updated every time the session information is updated by the Megaco protocol.

  FIG. 8 shows an outline of processing when the VoIP control unit (# 1) 41 is faulty. The VoIP control unit (standby) 44 reads the VoIP control unit (# 1) 41 portion of the context information table managed by itself during the switching operation, and sets it in hardware [DSP (Digital Signal Processor etc.)]. In the state matching process from the MGC 5, complete synchronization between the MGC5-VoIP control unit (standby) 44 is performed.

  As the media gateway device as described above, there are technologies described in Patent Documents 1 and 2 below. Patent Document 1 discloses a CA (Call Agent) that performs call control in an IP telephone network for establishing voice communication, and a media gateway device that transmits and receives voice data as IP packets. A system including is described.

  In Patent Document 2, in order to provide VoIP voice communication that connects a fixed telephone network and an IP network, the CA controls a media gateway device to realize a telephone service between the fixed telephone network and the IP network. The system to be described is described.

JP 2006-050250 A JP-A-2005-333312

  However, in the media gateway apparatus related to the present invention described above, since the call control management unit is included in the VoIP control unit of N + 1 redundant configuration (N is an integer of 2 or more), the failure of the VoIP control unit and the MGC When there is contention with Megaco reception, there is a problem that the context information cannot be taken over by the VoIP control unit (standby system). In order to overcome this problem, the media gateway device related to the present invention requires a state matching process with the MGC, and there is a problem that it takes a long time to solve the problem.

  Further, in the media gateway device related to the present invention, since the context information of all active VoIP control units must be held in the call control management unit (standby) at all times, the VoIP control unit (standby) There is a problem in that it cannot be configured in common with the active VoIP control unit. Alternatively, when the VoIP control unit (standby) is configured in common with the active VoIP control unit, it is necessary to mount a memory having a capacity larger than necessary in the active VoIP control unit.

  Furthermore, in the media gateway apparatus related to the present invention, VoIP control for relaying voice packets is necessary because a process for synchronization and a function for the synchronization are always required between the active system and the standby system of the VoIP control unit. There is a problem that an extra load is applied to the part.

  That is, in the media gateway device related to the present invention, the VoIP DSP installed in the VoIP control unit is expensive, and in order to increase the price competitiveness of the product, the VoIP control unit is not a duplex configuration. In general, an N + 1 redundant configuration is employed.

  In N + 1 redundant switching, it is necessary to have all the information on the active system in advance in the standby system, and the information is transferred to the standby system every time the information is updated. If the active system fails before and during information transfer to the standby system, there is a possibility that the information held in the standby system and the information on the active system will not match. In this case, the only active system that holds accurate information is a failure, the information in the media gateway device cannot be corrected, and it is only possible to rely on status matching processing (Audidate) from the MGC. It takes a considerable amount of time to take over correctly.

  Further, in the media gateway apparatus related to the present invention, since it is necessary to have all the information on the active system in the standby system, the standby system requires a larger memory capacity than the active system. In order to prepare a dedicated device or to make the active system and the standby system a common device, it is necessary to install a memory having an unnecessary capacity as the active system, which causes a cost increase. Note that the above-mentioned problems cannot be solved because Patent Documents 1 and 2 do not mention the redundant configuration of the media gateway device.

  Accordingly, an object of the present invention is to provide a media gateway device, a communication system, and a redundancy method used for them that can solve the above-described problems, minimize the cost increase, and make the reliability similar to a duplex configuration. There is to do.

The media gateway apparatus according to the present invention includes a VoIP (Voice over Internet Protocol) control unit for active and standby systems that performs at least RTP (Real-time Transport Protocol) packetization of voice data and media conversion of RTP packets into voice data. When,
A call control management means having a duplex configuration for setting information necessary for establishing a VoIP session in the VoIP control means,
Information set in the VoIP control unit when a failure occurs in the active VoIP control unit is set in the backup VoIP control unit by the information call control management unit.

  A communication system according to the present invention includes the above media gateway device.

The redundancy method of the media gateway apparatus according to the present invention includes a VoIP (Voice over Internet Protocol) for a working system and a standby system that perform at least RTP (Real-time Transport Protocol) packetization of voice data and media conversion to voice data of RTP packets. ) Providing a control means and a call control management means having a duplex configuration for setting information necessary for establishing a VoIP session in the VoIP control means;
Information set in the VoIP control unit when a failure occurs in the active VoIP control unit is set in the backup VoIP control unit by the information call control management unit.

  By adopting the configuration and operation as described above, the present invention has the effect of minimizing the cost increase and making the reliability comparable to the duplex configuration.

  Next, embodiments of the present invention will be described with reference to the drawings. First, an outline of a media gateway (MGW) device according to the present invention will be described. In the media gateway device according to the present invention, the call control management unit is separated from the VoIP (Voice over Internet Protocol) control unit, and the call control management unit is configured in a duplex configuration so that accurate information can be obtained from the active system when a failure occurs. It is characterized by taking over to the standby system, shortening the switching time from the active system to the standby system, and shortening the silence time.

  In the media gateway apparatus according to the present invention, the Megaco protocol [RFC (Request For Comments) 3015, ITU-T (International Telecommunication Union-Telecommunication Standards.) Is used by MGC (Media Gateway Control). 248], media conversion is performed.

  In the media gateway device according to the present invention, the active VoIP control unit and the standby VoIP control unit have an N + 1 redundant configuration (N is an integer of 2 or more). In addition to these VoIP control units, A line interface unit, a call control management unit, and a switch (SW) are provided.

  These VoIP control units are equipped with a VoIP DSP (Digital Signal Processor) inside, and RTP (Real-time Transport Protocol) packets of voice data received from the circuit-switched network side via a circuit interface (ITF) unit. On the other hand, it has functions such as media conversion, codec conversion, echo canceller, etc. for converting RTP into voice data on the circuit switching network side, and an interface function with an IP (Internet Protocol) network for transmitting and receiving RTP. The line interface unit has an interface function with a circuit switching network.

  The call control management unit receives the Megaco protocol from the MGC, manages call processing information, and has a function of setting information necessary for establishing a VoIP session in the VoIP control unit, and a redundancy control function of the VoIP control unit .

  The switch has a communication function and a switching function for the call control management unit, the VoIP control unit, and the line interface unit in the media gateway device to communicate with each other.

  The layer 2 switch (L2SW; Layer 2 Switch) can continue the service by taking over the IP address of the failed VoIP control unit when a failure occurs in the active VoIP control unit and switching to the standby VoIP control unit It has the function of the layer 2 switch for doing so.

  As described above, in the present invention, by performing information necessary for call processing in the call control management unit having a duplex configuration, the silence time is minimized at the time of failure switching of the VoIP control unit in the N + 1 redundant configuration, and the active system Information can be accurately transferred to the standby system.

  The present invention maintains the price advantage of the N + 1 redundant configuration of the VoIP control unit by separating the Megaco termination function and the call processing function from the VoIP control unit and arranging the call processing control unit having the call processing function in a duplex configuration. On the other hand, the disadvantage of the N + 1 redundant configuration of incomplete synchronization is eliminated, and the silent time can be shortened by redundant switching.

  FIG. 1 is a block diagram showing the configuration of a media gateway device according to the first embodiment of the present invention. In FIG. 1, a media gateway device (MGW) 1 includes call control management units 11 and 12, a switch 13, VoIP control units 14 to 16, a VoIP control unit (standby) 17, and a line interface (ITF) unit. 18 and 19.

  The call control management units 11 and 12 are connected to the MGC 2, and the VoIP control units 14 to 16 and the VoIP control unit (standby) 17 are connected to the IP network 100 via the layer 2 switch (L2SW) 3, and the line interface unit Reference numerals 18 and 19 are connected to the circuit switching network 200.

  The line interface units 18 and 19 have an interface function with the line switching network 200. The VoIP control units 14 to 16 and the VoIP control unit (reserved) 17 include an interface function with the IP network 100 and a VoIP function (voice data RTP packetization, media conversion from RTP to voice data, codec conversion, echo canceller, etc. )have.

  The call control managers 11 and 12 perform Megaco communication with the MGC 2, call processing control functions, and redundancy management functions of the VoIP controllers 14 to 16 and the VoIP controllers (standby) 17 and the line interface units 18 and 19. And have. The switch 13 has a switch function for performing communication within the media gateway device 1.

  2 to 6 are diagrams showing the operation of the media gateway device 1 according to the first embodiment of the present invention. The redundant configuration in the media gateway device 1 according to the first embodiment of the present invention will be described with reference to FIGS.

  Referring to FIG. 2, a communication route of context information that is set from MGC 2 to Megaco in the media gateway device 1 and necessary for establishing a VoIP session is shown. Megaco from MGC2 terminates at call control managers (# 0, # 1) 11, 12. The call control managers (# 0, # 1) 11 and 12 have a duplex configuration, and communication with the MGC 2 is performed only on the active system side.

  The call control managers (# 0, # 1) 11, 12 send the context information necessary for establishing a VoIP session from Megaco to the VoIP controllers (# 1- # 3) 14-16 and VoIP controller (standby) 17. The voice communication between the circuit switching network 200 and the IP network 100 is enabled. Between the call control managers (# 0, # 1) 11 and 12, there is a route for synchronizing context information between the active system and the standby system.

  Referring to FIG. 3, the operation at the time of receiving Megaco from MGC 2 in the media gateway device 1 is shown. The call control manager (# 0) 11 terminates Megaco when operating in the active system, and sets the context information in the VoIP controller (# 1) 14 for establishing voice communication.

  Further, in the event that a failure occurs in the call control management unit (# 0) 11, the standby side call processing control unit (# 1) 12 is also connected to the standby side call processing control unit (# 0) 11, as in the case of the call control management unit (# 0) 11. Context information is set, and the call control manager (# 0) 11 (active system) and the call control manager (# 1) 12 (standby system) are synchronized.

  Referring to FIG. 4, there is shown an example of voice communication between the circuit switched network 200 and the IP network 100 before a failure occurs in the media gateway device 1. Referring to FIG. 5, the operation of the call control management unit (# 0) 11 when a failure occurs in the VoIP control unit (# 1) 14 used as the active system in the media gateway device 1 is shown. FIG. 6 shows an example of voice communication between the circuit switched network 200 and the IP network 100 after system switching in the media gateway apparatus 1.

  Next, the operation of each function of the media gateway device 1 shown in FIG. 1 will be described with reference to FIGS.

  FIG. 2 shows a communication route of context information necessary for establishing a VoIP session. FIG. 3 shows a context information setting operation using the communication route shown in FIG. In FIG. 3, Megaco received from MGC2 is terminated at call control manager (# 0) 11 (active system).

  The call control management unit (# 0) 11 hunts the VoIP control unit (# 1) 14 that performs voice communication, and sets context information necessary for voice communication in the VoIP control unit (# 1) 14. The call processing control unit according to the present embodiment employs a duplex system [call control management unit (# 0) 11, call control management unit (# 1) 12] in order to improve reliability.

  In order to synchronize with the standby call control management unit (# 1) 12, the active call control management unit (# 0) 11 performs call control in the same manner as the setting to the VoIP control unit (# 1) 14. The context information is also set in the management unit (# 1) 12. The context information table represents the context information managed by each device, and the context information of the VoIP control unit (standby) 17 is empty.

  During voice communication between the IP network 100 and the circuit switching network 200 using the VoIP control unit (# 1) 14 and the line interface unit (# 0) 18 (see FIG. 4), the VoIP control unit (# 1 ) 14 will be described with reference to FIG.

  In FIG. 5, when a failure occurs in the VoIP control unit (# 1) 14 [(1) in FIG. 5], the call control management unit (# 0) 11 performs the health implemented for each functional unit. The occurrence of the failure is detected by checking [(2) in FIG. 5].

  When the call control management unit (# 0) 11 detects a failure of the VoIP control unit (# 1) 14, the call control management unit (# 0) 11 reads the information of the VoIP control unit (# 1) 14 from the context information table held in its own circuit. [(3) in FIG. 5] notifies the VoIP control unit (reserve) 17 [(4) in FIG. 5]. The call control management unit (# 0) 11 instructs the line interface unit (# 0) 18 to switch the transmission destination from the VoIP control unit (# 1) 14 to the VoIP control unit (standby) 17 [FIG. 5 (5)].

  The VoIP control unit (standby) 17 sets the context information of the VoIP control unit (# 1) notified from the call control management unit (# 0) 11 in an empty context information table [(6) in FIG. ]. As a result, the VoIP control unit (standby) 17 takes over the IP address for the IP network 100 of the VoIP control unit (# 1) 14 and causes the layer 2 switch 3 to perform MAC learning on its own MAC (MAC) address [FIG. (7)], the switching process from the VoIP control unit (# 1) 14 to the VoIP control unit (standby) 17 is terminated.

  Thereafter, in the present embodiment, as shown in FIG. 6, the VoIP control unit (standby) 17 becomes the active system instead of the VoIP control unit (# 1) 14, and communicates with the line interface unit (# 0) 18. And continue the voice communication service.

  As described above, in this embodiment, since the VoIP control unit alone has N + 1 redundancy, complete synchronization between the active system and the standby system is not possible (information may not be transferred to the standby system at the time of active failure). Since the context information is set from the call control manager during the system switching operation of the VoIP controller, complete synchronization can be achieved.

  Also, in this embodiment, a VoIP DSP is installed, and the most expensive VoIP control unit in the system is not duplicated, but N + 1 redundant, so the reliability is higher than before. Even if it improves, the cost increase can be suppressed.

  Furthermore, in this embodiment, the call control management unit is separated from the VoIP control unit and duplicated, and the context information of all VoIP control units is managed by these call control management units. ) Requires a minimum amount of context information to be set at the time of the switching operation, and does not require the state matching process after switching, so that the switching time between the active system and the standby system can be shortened.

  That is, in the present embodiment, as described above, the call control management unit is separated from the VoIP control unit and is duplicated, and the context information of all the VoIP control units is managed by these call control management units, thereby reducing the cost. It is possible to minimize the increase and make the reliability similar to the duplex configuration.

It is a block diagram which shows the structural example of the media gateway apparatus by the 1st Embodiment of this invention. It is a figure which shows operation | movement of the media gateway apparatus by the 1st Embodiment of this invention. It is a figure which shows operation | movement of the media gateway apparatus by the 1st Embodiment of this invention. It is a figure which shows operation | movement of the media gateway apparatus by the 1st Embodiment of this invention. It is a figure which shows operation | movement of the media gateway apparatus by the 1st Embodiment of this invention. It is a figure which shows operation | movement of the media gateway apparatus by the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the media gateway apparatus relevant to this invention. It is a figure which shows operation | movement of the media gateway apparatus relevant to this invention.

Explanation of symbols

1 Media gateway device
2 MGC
3 Layer 2 switch 11, 12 Call control management unit 13 Switch 14-16 VoIP control unit 17 VoIP control unit (standby)
18, 19 Line interface section 100 IP network 200 Line switching network

Claims (11)

VoIP (Voice over Internet Protocol) control means for active and standby systems that perform at least RTP (Real-time Transport Protocol) packetization of voice data and media conversion of RTP packets into voice data;
A call control management unit having a duplex configuration for setting information necessary for establishing a VoIP session in the VoIP control unit;
A media gateway apparatus characterized in that, when a failure occurs in the active VoIP control means, information set in the VoIP control means is set in the standby VoIP control means by the call control management means.   2. The media gateway apparatus according to claim 1, wherein the working VoIP control means and the standby VoIP control means have an N + 1 redundant configuration (N is an integer of 2 or more).   3. The VoIP control means performs at least RTP packetization of voice data received from the circuit switched network side and media conversion of RTP packets into voice data on the circuit switched network side. The media gateway device described.   The call control management means receives Megaco protocol from MGC (Media Gateway Control), manages call processing information, and sets information necessary for establishing a VoIP session in the VoIP control means. The media gateway device according to any one of claims 1 to 3.   5. The media gateway device according to claim 1, wherein the call control management unit performs redundancy control of the VoIP control unit.   A communication system comprising the media gateway device according to any one of claims 1 to 5. Necessary for establishing a VoIP session with active and standby VoIP (Voice over Internet Protocol) control means for converting at least voice data into RTP (Real-time Transport Protocol) packets and converting media into voice data of RTP packets. A duplex control call control management means for setting information in the VoIP control means,
A redundancy method for a media gateway device, characterized in that, when a failure occurs in the active VoIP control means, information set in the VoIP control means is set in the standby VoIP control means by the call control management means.   8. The redundancy method for a media gateway device according to claim 7, wherein an N + 1 redundant configuration (N is an integer of 2 or more) is configured by the active VoIP control means and the standby VoIP control means.   9. The VoIP control means performs at least RTP packetization of voice data received from the circuit switched network side and media conversion of RTP packets into voice data on the circuit switched network side. A redundancy method for the described media gateway device.   The call control management means receives Megaco protocol from MGC (Media Gateway Control), manages call processing information, and sets information necessary for establishing a VoIP session in the VoIP control means. The redundancy method for a media gateway device according to any one of claims 7 to 9.   11. The redundancy method for a media gateway device according to claim 7, wherein redundancy control of the VoIP control unit is performed by the call control management unit.

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