JP5125207B2 - IP telephone communication system and IP telephone communication method - Google Patents

Description

  The present invention relates to a telephone communication system using an IP network, and more particularly to a system including a redundantly configured server device.

  As a call control protocol applied to a telephone communication system using an IP network, for example, there is a SIP (Session Initiation Protocol) compliant with RFC3261. Further, a redundant server configuration is known as a countermeasure for server failure in a telephone communication system. The redundant configuration is to deploy a server as a substitute in addition to a server to be used preferentially.

  In a system employing a redundant configuration, when a failure occurs in a normal server due to a power failure or the like and the operation stops, the standby server automatically operates. Thereafter, the telephone set as the client communicates by connecting to the standby server.

A technique using the SIP server having the redundant configuration as described above is described in, for example, Patent Document 1 described later. The system described in Patent Document 1 registers the priority order and availability information of each SIP server in the IP telephone terminal, and when a response to a call request to the SIP server registered to be available is not obtained, The registration of the server is changed to unusable and a call request is made to another server. As a result, efficient use of a plurality of SIP servers is achieved.
JP 2006-237950 A

  However, in the system described in Patent Document 1, it is necessary for a telephone set as a client to always manage information of a plurality of SIP servers, so that a processing load is applied to the telephone set. In addition, even a SIP server registered in a telephone as usable can actually be unavailable, and it is difficult to make the registered contents on the telephone side correspond to the current state of the server.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for a client to appropriately recognize the current state of a server in an IP telephone communication system.

IP telephone communication system according to the present invention comprises a pair of server device connected to the client device and the IP network connected to the IP network, wherein the client device, of its own device to one of the pair of the server device comprising means for transmitting a first call control message for registering the location information, and means for setting a destination to the first call control messages, each of the pair of the server device, the client device and means for notifying the recording and the location information the position information to the own device when receiving the first call control message to the other server device from the means for monitoring the change in operating state of the other server devices The second call control message for instructing the client device to set the destination of the first call control message as its own device. Means for transmitting to the client device when the operating state of the server device changes, and the client device is instructed by the second call control message when receiving the second call control message. A first call control message with a destination set is transmitted.

  According to the present invention, the client device can grasp the server device that is the registration destination of the position information without managing the operating state of each server device. As a result, the processing load on the client device is reduced, and location registration in the server device can be completed quickly.

  FIG. 1 shows a system configuration of an embodiment of the present invention. The system 10A includes a normal IP telephone device 100 and a standby IP telephone device 101 connected to an IP network 103 through which IP packets are transmitted, and a plurality of telephones 102.

  The normal and standby IP telephone devices (100, 101) correspond to a pair of server devices in the IP telephone communication system of the present invention. The spare IP telephone device 101 is prepared as a substitute when a failure occurs in the normal IP telephone device 100. The telephone 102 corresponds to the client device in the present invention.

  FIG. 2 shows a functional configuration of each IP telephone apparatus (100, 101). The LAN interface 201 is an interface for transmitting and receiving IP packets via the IP network 103. The IP packet analysis unit 202 analyzes the received IP packet and sorts the packet contents into a SIP message, shared data, a keep alive message, and the like. In addition, an IP packet is generated during packet transmission. The call control unit 204 has a function of performing SIP message call control as a SIP server function.

  The SIP message processing unit 203 analyzes the SIP message distributed by the IP packet analysis unit 202 to acquire the location information (IP address) of the telephone 102 and registers it in the telephone location information storage unit 205. The telephone location information storage unit 205 has a telephone location information management table 301 as shown in FIG. 3A for registering location information using an extension number as a key. When the registered content of the telephone location information management table 301 is updated, the telephone location information storage unit 205 notifies the retained information sharing processing unit 206 to that effect.

  The redundant IP telephone apparatus position information storage unit 207 stores the position information (IP address) of the other IP telephone apparatus as redundant IP telephone apparatus position information 302 as shown in FIG. Specifically, the location information (302) of the backup IP phone device 101 is stored in the normal IP phone device 100, and the backup IP phone device 101 stores the location information of the normal IP phone device 100. Location information (302) is stored. These pieces of information are input in advance by the administrator or the like via the user interface unit 209.

  When the retention information sharing processing unit 206 receives an update notification of the telephone location information management table from the telephone location information storage unit 205, the retained information sharing processing unit 206 refers to the redundant IP telephone device location information storage unit 207 to the backup IP phone device 101. Notify the updated contents. The backup IP telephone apparatus 101 stores the content notified from the normal IP telephone apparatus 100 in the telephone position information storage unit 205.

  The keep alive processing unit 208 has a function of referring to the redundant IP telephone device location information storage unit 207 and transmitting / receiving a keep alive message to the other IP telephone device. The keep-alive message is a conventionally known message for monitoring each other's operating state between devices that exchange it. When the keep-alive processing unit 208 of the backup IP telephone apparatus 101 detects a timeout during a preset period, that is, when it detects that the normal IP telephone apparatus 100 is stopped, the call control unit 204 To notify.

  FIG. 4 shows a functional configuration of the telephone 102. The LAN interface 401, the IP packet analysis unit 402, the SIP message processing unit 403, and the call control unit 404 of the telephone set 102 basically perform the same functions as those of the IP telephone apparatus shown in FIG. The telephone 102 transmits a SIP message for registering its own location information (IP address) 410 to the IP address of the IP telephone device 100 or the IP telephone device 101 stored as the registration destination information 411.

  The overall operation of the system will be described with reference to the sequence shown in FIG. In advance, in each IP telephone apparatus (100, 101), the user interface 209 stores the IP address of the other IP telephone apparatus as redundant IP telephone apparatus location information 302 (FIG. 3). In the registration destination information 411 of the telephone 102, the IP address of the normal IP telephone device 100 is set as an initial value.

  Backup IP telephone apparatus 101 monitors whether IP telephone apparatus 100 is operating by sending and receiving keepalive IP packets with normal IP telephone apparatus 100 (step S1). During this time, when the user of the telephone set 102 performs an operation to make an IP call, the telephone set 102 transmits a “REGISTER” SIP message for registering its own location information to the normal IP telephone device 100 (step S2). ). This “REGISTER” message corresponds to the first call control message in the present invention.

  When receiving the “REGISTER” message from telephone 102, normal IP telephone apparatus 100 returns a “200 OK” SIP message indicating acceptance of registration (step S3). Further, the IP address of the telephone set 102 included in the “REGISTER” message is extracted and registered in the telephone position information management table 301 (FIG. 3) (step S4). The IP telephone apparatus 100 notifies the backup IP telephone apparatus 101 of the table update data by this registration process (step S5).

  The backup IP telephone apparatus 101 stores the update data from the normal IP telephone apparatus 100 in its own telephone position information management table 301 (step S6). As a result, the table information is shared between the normal system and the standby system.

  After that, when the standby IP telephone apparatus 101 detects that the normal IP telephone apparatus 100 has stopped operating in the keep-alive process (step S7), the telephone 102 is directed to the local apparatus to operate on behalf of the normal system. Instructs registration of location information. That is, a SIP message for instructing to change the location information registration destination from the normal system to the standby system is transmitted to the telephone set 102 (step S8).

  For the SIP message for changing the registration destination of the position information, “OPTIONS” whose transmission timing is arbitrary is used. The “OPTIONS” message corresponds to the second call control message in the present invention. As the destination of the “OPTIONS” message, the IP address of the telephone set 102 notified from the normal IP telephone apparatus 100 and stored in the telephone position information management table 301 is set.

  When the telephone set 102 receives an instruction to change the registration destination from the backup IP telephone apparatus 101 using the “OPTIONS” message, it returns “200 OK” indicating that the registration is accepted (step S9), and the registration destination information of the own device. 411 is changed from the normal system address to the standby system address (step S10). Then, the location information is newly registered by transmitting a “REGISTER” message to the backup IP telephone apparatus 101 (steps S11 and S12).

  With reference to the flowchart shown in FIG. 6, the operation of normal IP telephone apparatus 100 in the series of processes (FIG. 5) will be described. When the IP telephone apparatus 100 receives an IP packet from the IP network 103 via the LAN interface 201, the IP packet analysis unit 202 analyzes the IP packet (step A1) and identifies the message type (step A2). If the received IP packet is a SIP message, the SIP message processing unit 203 analyzes the message (step A3) and identifies the message type (step A4).

  If the message type is “REGISTER” as a result of the identification, the location information (IP address) of the telephone 102 that is the message transmission source is extracted from the message (step A5) and registered in the phone location information management table 301. (Step A6). In addition, IP telephone apparatus 100 transmits “200 OK” indicating that registration of location information is permitted to telephone set 102 (step A7).

  When the telephone location information management table 301 is updated in the normal IP telephone device 100 as described above, the retained information sharing processing unit 205 refers to the redundant IP telephone device location information 302 (step A8), and the standby system. Update data is transmitted to the IP address of IP telephone apparatus 101 (step A9).

  On the other hand, when the identification result (step A2) of the IP packet received by the normal IP telephone device 100 is a keep-alive message, the keep-alive processing unit 208 analyzes the message (step A10) and extracts transmission source information. (Step A11). Then, the keep alive processing unit 208 transmits a keep alive message response to the backup IP telephone apparatus 101 as the transmission source (step A12).

  With reference to the flowchart shown in FIG. 7, the operation of the standby system with respect to the normal system will be described. When the backup IP telephone apparatus 101 receives an IP packet from the IP network 103 via the LAN interface 201, the IP packet analysis unit 202 performs IP packet analysis (step B1) and identifies the message type (step B2). ).

  As a result of the identification, if the update data is from the normal IP telephone device 100, the holding information sharing unit 205 analyzes the update data and extracts the IP address of the telephone 102 (steps B3 and B4). Is registered in the telephone position information management table 301 (step B5).

  If the received IP packet is a keep-alive message response from the normal IP telephone device 100, the keep-alive processing unit 208 analyzes the keep-alive message and extracts transmission source information (steps B6 and B7). Then, the keep alive timer is updated (step B8), and a new keep alive message is transmitted to the normal IP telephone device 100 (step B9).

  With reference to the flowchart shown in FIG. 8, the operation of standby IP telephone apparatus 101 when a failure occurs in the normal system will be described. When the normal system operation stops and the keep-alive timer times out in the backup IP telephone apparatus 101 (step C1), the call processing unit 204 determines that the normal system operation has stopped. In response to this, the backup IP telephone apparatus 101 starts operating as a normal system.

  The SIP message processing unit 204 searches the telephone location information management table 301 (step C2). When the registered IP address exists, the SIP message processing unit 204 reads out the IP address and reads the above-mentioned “OPTIONS” message with the address as the destination. Transmit (steps C3 and C4). In the “OPTIONS” message to be transmitted, the IP address of the backup IP telephone apparatus 101 is set. As a result, the telephone 102 is instructed to change the location information registration destination from the normal IP telephone device 100 to the standby IP telephone device 101.

  The operation of the telephone set 102 instructed to change the registration destination will be described with reference to the flowchart shown in FIG. The telephone 102 analyzes the received SIP message and identifies the message type (steps D1 and D2).

  If the message type is “OPTIONS” as a result of the identification, the IP address of the backup IP telephone device 101 that is the transmission source of the message is extracted from the message (step D3), and a response to “OPTIONS” is sent to the extracted address. A message (200 OK) is transmitted (step D4). Furthermore, a new location registration is performed by transmitting a “REGISTER” message to the backup IP telephone apparatus 101 (step D5).

  Note that the normal IP phone device 100 that has stopped operating may immediately return to the normal system when the failure is resolved and becomes operational, but the IP that is currently operating as the normal system The telephone device 101 may operate as a backup system. In that case, IP telephone apparatus 100 operates in accordance with the procedure of the standby system (101).

  As described above, in the above-described embodiment, the standby IP telephone apparatus 101 instructs the telephone 102 to change the registration destination of the location registration when the normal operation is stopped. Therefore, the telephone 102 can grasp the registration destination of the location information without managing the operating state of each IP telephone device. As a result, the processing load on the telephone 102 can be reduced and the location registration can be completed quickly. In addition, even if there is a change such as the addition of a spare IP phone device or an address change, the change can be flexibly handled on the telephone side.

  In the above embodiment, the registration destination of the location information of the client device is changed when one server device (100) is stopped. Instead, the processing load status of one server device is registered. You may use for judgment of change. The embodiment will be described below.

  FIG. 10 shows a system configuration of another embodiment according to the present invention. The system 10B of this embodiment is a system in which both the pair of IP telephone devices 500 and the IP telephone device 501 operate as normal systems. Each telephone 502 performs location registration with the IP telephone apparatus 500 or the IP telephone apparatus 501 based on the registration destination information 411 (FIG. 4).

  The operations of IP telephone apparatus 500 and IP telephone apparatus 501 will be described with reference to the flowchart shown in FIG. Here, it is assumed that the IP telephone apparatus 501 has a higher processing capability than that of the IP telephone apparatus 500.

  When the IP telephone device 500 newly registers the position information of the telephone 502 in the telephone position information management table 301 (FIG. 3) (step E1), as in the above-described embodiment, the update data is transferred to the other IP telephone device. Notify 501 (step E2).

  Each time registration is performed, IP telephone apparatus 500 determines whether or not the current number of registrations exceeds a preset upper limit number (step E3). If the number of registrations exceeds the upper limit as a result of the determination, the IP telephone device 501 is notified to that effect (step E4), and the registered location information is deleted from the phone location information management table 301 (step E5). IP telephone apparatus 500 limits the number of connections of telephone 502 by repeating the above process while the number of registrations exceeds the upper limit.

  On the other hand, IP telephone apparatus 501 once stores the location information of the new registration notified from IP telephone apparatus 500 (step E6), and recognizes whether the number of registrations in IP telephone apparatus 500 has exceeded the upper limit. Specifically, after receiving the update data, if there is no notification that the upper limit has been exceeded for a predetermined period (step E7: No), it is determined that the upper limit has not been exceeded yet, that is, the IP telephone device 500 is not overloaded. To do. In this case, IP telephone apparatus 501 deletes the location information of the update data notified from IP telephone apparatus 500 from the table (step E10).

  Further, after receiving the update data from the IP telephone device 500 and receiving a notification that the upper limit has been exceeded (step E7: Yes), the IP telephone device 501 reads the position information of the target telephone 502 from the table ( In step E8), the aforementioned “OPTIONS” message is transmitted to the telephone 502 (step E9). Receiving the “OPTIONS” message, the telephone 502 changes the registration destination from the IP telephone apparatus 500 to the IP telephone apparatus 501 and registers location information in the IP telephone apparatus 501.

  According to the embodiment described with reference to FIGS. 10 and 11, when the number of connections processed by the IP telephone apparatus 500 exceeds the upper limit, the other IP telephone apparatus 501 is controlled to automatically substitute for the excess. be able to. Thereby, the processing load in the system can be distributed.

  In each of the above embodiments, the call control protocol of the IP network is SIP conforming to RFC3261, but the scope of the present invention is not limited to SIP, but other call control protocols such as H.323 or MGSP. May be.

  The present invention is not limited to the implementation as a system, and may be implemented as a computer program corresponding to the processing procedure of the IP telephone apparatus and the telephone in each of the above embodiments.

1 is a configuration diagram of a system according to an embodiment of the present invention. It is a block diagram which shows the function structure of the IP telephone apparatus in embodiment. It is explanatory drawing of the telephone position information management table and redundant IP telephone apparatus position information in embodiment. It is a block diagram which shows the function structure of the telephone set in embodiment. It is a sequence diagram which shows the system operation | movement of embodiment. It is a flowchart which shows the process of the normal system IP telephone apparatus in embodiment. 5 is a flowchart showing processing of a standby IP telephone apparatus in the embodiment. 5 is a flowchart showing processing of a standby IP telephone apparatus in the embodiment. It is a flowchart which shows the process of the telephone set in embodiment. It is a block diagram of the system of other embodiment which concerns on this invention. It is a flowchart which shows the process of the IP telephone apparatus in other embodiment.

Explanation of symbols

10A, 10B system
100,101,500,501 IP telephone equipment (server equipment)
102,502 Telephone (client device)
103,503 IP network
201,401 LAN interface
202,402 IP packet analyzer
203,403 SIP message processor
204,404 Call controller
205 Telephone location information storage
206 Retained information sharing processor
207 Redundant IP telephone equipment location information storage
208 Keep alive processing part
209 User interface
301 Telephone location information management table
302 Redundant IP phone device location information
410 Location information
411 Registration information

Claims (16)

A pair of server device connected to the client device and the IP network connected to the IP network,
Wherein the client device comprises means for transmitting a first call control message for registering the location information of its own device to one of the pair of the server, means for setting a destination to the first call control messages And
Each of the pair of the server apparatus includes a means for notifying the recording and the location information the position information to the own device when receiving the first call control message from the client device to the other server apparatus, the other A means for monitoring a change in the operating state in the server device, and a second call control message for instructing the client device to set the destination of the first call control message as its own device. Means for transmitting to the client device when
When receiving the second call control message, the client apparatus transmits a first call control message in which a destination designated by the second call control message is set. .   The pair of server devices monitor whether or not the operation is stopped as a change in operation state in the other server device, and when the operation stop is detected, the second server device transmits the second call control message to the client device. The IP telephone communication system according to claim 1.   The pair of server devices monitor whether or not the registration number of the position information exceeds the upper limit as a change in the operating state in the other server device, and when detecting that the registration number exceeds the upper limit, 2. The IP telephone communication system according to claim 1, wherein a call control message is transmitted to the client device.   4. The IP telephone communication system according to claim 1, wherein each of the call control messages is a SIP (Session Initiation Protocol) compliant message. And means for notifying the recording and the location information the position information to the own device when receiving the first call control message for registering the location information of the connected client device to an IP network to another server device, Means for monitoring a change in operating state in the other server device, and a second call control message for instructing the client device to use the destination of the first call control message as the own device. And a means for transmitting to the client device when the operating state of the device changes.   6. The second call control message is transmitted to the client device when the operation stop is monitored as a change in the operation state in the other server device, and the operation stop is detected. Server device.   As a change in operating state in the other server device, it is monitored whether or not the number of registered position information exceeds the upper limit, and when it is detected that the registered number exceeds the upper limit, the second call control message is sent to the client The server apparatus according to claim 5, wherein the server apparatus transmits the apparatus to the apparatus.   8. The server apparatus according to claim 5, wherein each call control message is a message conforming to SIP (Session Initiation Protocol).   A program that causes a computer to function as the server device according to any one of claims 5 to 8. Means for transmitting a first call control message for registering location information of the own device to one of a pair of server devices according to any one of claims 5 to 8 connected to an IP network; and means for setting a destination to the first call control messages,
When receiving the second call control message for instructing the destination of the first call control message to the own device, the first call control message in which the destination indicated by the second call control message is set A client device characterized by transmitting a message.   11. The client apparatus according to claim 10, wherein each call control message is a message conforming to SIP (Session Initiation Protocol).   A program for causing a computer to function as the client device according to claim 10 or 11. In a system comprising a client device connected to an IP network and a pair of server devices connected to the IP network ,
Monitoring a change in the operating state of the other server device between the pair of server devices;
The client device transmits a first call control message for registering location information of the own device to one of the pair of server devices,
The recording and the location information to the server apparatus that has received the first call control message from the client device own device the location information notified to the other server apparatus,
A second device for instructing the client device to set the destination of the first call control message as its own device when the server device notified of the location information detects a change in the operating state of the other server device. Send a call control message
When the client apparatus receives the second call control message, the client apparatus transmits a first call control message in which a destination designated by the second call control message is set. .   The pair of server devices monitor whether or not operation is stopped as a change in operation state in the other server device, and when the operation stop is detected, the second call control message is transmitted to the client device. The IP telephone communication method according to claim 13.   When the pair of server devices monitor whether or not the registration number of the position information exceeds the upper limit as a change in the operating state of the other server device, and detects that the registration number exceeds the upper limit, 14. The IP telephone communication method according to claim 13, wherein a call control message is transmitted to the client device.   16. The IP telephone communication method according to claim 13, wherein each call control message is a message conforming to SIP (Session Initiation Protocol).

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