JP2014072795A - Call control device, registration processing method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reflect a state of each terminal subordinate to a second call control device in a first call control device in real time, in a communication system in which the second call control device connected to a second communication network is connected to the first call control device connected to a first communication network.SOLUTION: A call control device used as a second call control device comprises: reception means for receiving a registration message including a terminal telephone number which is a telephone number of a terminal and terminal address information which is address information on the terminal, from the terminal; registration processing means for storing the terminal telephone number and the terminal address information included by the received registration message in registration information storage means; message creation means for creating a registration message obtained by replacing the terminal address information in the received registration message with address information of the call control device; and transmission means for transmitting the created registration message to the first call control device.

Description

  The present invention relates to IP telephone communication based on SIP (Session Initiation Protocol), and more particularly to REGISTER processing for registering terminal address information in a call control device.

  In recent years, IP telephone communication technology using SIP has become widespread. In IP telephone communication using SIP, a SIP server, which is a call control device, is arranged in an IP network, and performs call control such as call establishment by sending and receiving SIP messages between terminals via the SIP server.

  In establishing a call, first, the transmission source terminal transmits a REGISTER message to the SIP server, and registers the telephone number and address information of the terminal in the SIP server. Similarly, the destination terminal registers its own number and address information in the SIP server. Thereafter, the source terminal sends an INVITE message requesting a call connection with the destination terminal to the SIP server, and the SIP server transfers the INVITE message to the destination terminal based on the registration information of the destination terminal. A call is established by transmitting and receiving a message including such processing, and a call can be established between the transmission source terminal and the destination terminal.

JP 2004-282115 A

  With the spread of IP telephone technology, more and more companies are introducing SIP servers called IP-PBXs instead of conventional PBXs. This SIP server enables extension calls and the like by IP telephone communication.

  Further, as shown in FIG. 1, by connecting a SIP server 20 connected to the communication network 2 to a SIP server 10 such as an IP-PBX connected to the communication network 1, the communication network 1 and the communication network 2 are connected. Services that enable extension calls across the network and extension calls within the communication network 2 are also being studied. In this case, for example, the communication network 1 is a communication network or a LAN provided by a fixed telephone carrier, and the communication network 2 is a communication network or the Internet provided by a mobile phone operator. That is, it is assumed that a terminal such as a business phone is fixedly connected to the communication network 1, but the communication network 2 is frequently connected and disconnected by a terminal such as a smartphone.

  In the example shown in FIG. 1, the SIP server 20 is a device positioned similarly to the terminal connected to the SIP server 10 when viewed from the SIP server 10, and sends itself to the SIP server 10 by sending a REGISTER message. Register with.

  The REGISTER message from the SIP server 20 to the SIP server 10 includes address information of the SIP server 20 (IP address, port number, etc. for connection to the SIP server 20) and a plurality of terminals that can be connected under the SIP server 20. Phone number. The REGISTER message from the SIP server 20 to the SIP server 10 is transmitted, for example, at a timing when the SIP server 20 is connected to the SIP server 10.

  In addition, the address information of the SIP server 20 and the telephone numbers of a plurality of terminals that can be connected to the SIP server 20 are fixedly registered in the SIP server 10, and the REGISTER process from the SIP server 20 to the SIP server 10 is performed. It is also possible to adopt a configuration that does not.

  However, in the above technique, a plurality of terminals are registered in the SIP server 10 regardless of whether or not the terminal address information is actually registered in the SIP server 20. There are problems as shown.

  As shown in FIG. 2, it is assumed that the SIP server 10 receives an INVITE message for requesting a call connection to the terminal 200 under the SIP server 20 from the terminal 100 under the SIP server 10 (step 101). Here, it is assumed that information of a plurality of terminals including the terminal 200 is registered in the SIP server 10, but address information of the terminal 200 is not registered in the SIP server 20. This corresponds to, for example, a case where the communication network 2 is a mobile phone network and the terminal 200 is out of a callable area.

  In such a case, the SIP server 10 that has received the INVITE message in step 101 transfers the INVITE message for the terminal 200 to the SIP server 20 in accordance with the registration information (step 102). However, since the address information of the terminal 200 is not registered in the SIP server 20, the SIP server 20 cannot transfer the INVITE message to the terminal 200 and returns an error response (steps 103 and 104).

  In the above technique, the SIP server 10 sends the INVITE message to the SIP server 20 wastefully without recognizing that the terminal 200 is not registered in the SIP server 20, and therefore transmits an error response to the terminal 100. It takes time to do this, and an extra packet is transmitted, which consumes extra communication resources.

  The present invention has been made in view of the above points. In a communication network in which a second call control device is connected to a first call control device, individual subordinates of the second call control device are provided. A technique that reflects the state of a terminal in the first call control device in real time and enables the first call control device to perform call control quickly according to the state of a terminal under the control of the second call control device. The purpose is to provide.

In order to solve the above problems, the present invention is such that a second call control device connected to a second communication network is connected to a first call control device connected to a first communication network. A call control device used as the second call control device in a communication system,
Receiving means for receiving a registration message including a terminal telephone number that is the telephone number of the terminal and terminal address information that is the address information of the terminal from the terminal;
Registration processing means for storing in the registration information storage means the terminal telephone number and the terminal address information in the registration message received by the receiving means;
Message creating means for creating a registration message by replacing the terminal address information in the registration message received by the receiving means with the address information of the call control device;
The call control device includes a transmission unit that transmits the registration message created by the message creation unit to the first call control device.

  For example, the first call control device is an IP-PBX that functions as a SIP server, and the call control device is a SIP server.

  The present invention can also be configured as a registration processing method executed by the call control device and a program for causing a computer to function as each means in the call control device.

  According to the present invention, in the communication network configured by connecting the second call control device to the first call control device, the state of each terminal under the second call control device is changed to the first call control. It is possible to provide a technique that allows the first call control device to perform call control promptly according to the state of a terminal under the control of the second call control device by reflecting it in the device in real time.

It is a figure for demonstrating the subject which this invention tends to solve. It is a figure for demonstrating the subject which this invention tends to solve. It is a block diagram of the communication system which concerns on embodiment of this invention. FIG. 3 is a functional configuration diagram of a call control device B according to an embodiment of the present invention. It is a figure for demonstrating operation | movement of the communication system which concerns on embodiment of this invention. It is a figure for demonstrating operation | movement of the communication system which concerns on embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below is only an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

(System configuration)
FIG. 3 shows a configuration example of the communication system according to the embodiment of the present invention. As shown in FIG. 3, the communication system according to the present embodiment has a configuration in which call control device B connected to communication network NB is connected to call control device A such as IP-PBX connected to communication network NA. The communication system enables an extension call between the communication network NA and the communication network NB and an extension call within the communication network B. In this communication system, for example, the communication network NA is a network or LAN provided by a fixed telephone carrier, and the communication network NB is a mobile phone network or the Internet provided by a mobile phone operator. As in the case of FIG. 1, a terminal such as a business phone is fixedly connected to the communication network NA. However, in the communication network NB, a situation in which connection and disconnection by a terminal such as a smartphone frequently occurs is assumed.

  In the present embodiment, both the call control device A and the call control device B shown in FIG. 3 are SIP servers that perform call control by SIP, but the call control protocol to which the present invention is applicable is limited to SIP. Instead, the call control device A and the call control device B may be devices other than the SIP server.

  Call control device B is a device connected to call control device A in the same position as a terminal connected to call control device A, and sends itself to call control device A by sending a REGISTER message to call control device A. sign up.

  FIG. 4 shows a functional block diagram of call control apparatus B according to the present embodiment. FIG. 4 mainly shows a part of the registration processing particularly related to the present invention in the call control apparatus B, and an existing function (not shown) for functioning as a SIP server that appropriately transmits and receives various SIP messages. Including.

  As shown in FIG. 4, the call control apparatus B according to the present embodiment includes a receiving unit 31, a terminal confirmation unit 32, a registration processing unit 33, a message creation unit 34, a transmission unit 35, a terminal information storage unit 36, registration information. A storage unit 37 is included.

  The receiving unit 31 is a functional unit that receives a registration message (specifically, a SIP REGISTER message) from the terminal. The terminal information storage unit 36 stores in advance identification information of a terminal permitted to connect to the call control device B (in this embodiment, a telephone number such as an extension number of the terminal). It has a function of confirming whether or not the transmission source terminal of the registration message is a valid terminal by collating the telephone number of the terminal included in the received registration message with the information stored in the terminal information storage unit 36. In addition, the password may be included in the registration message, and the validity of the terminal may be confirmed using the password as a target of verification.

  The registration processing unit 33 is a functional unit that stores the telephone number of the terminal included in the received registration message and the terminal address information (IP address, port number, etc.) in the registration information storage unit 37 in association with each other. For example, when the call control device B receives an incoming INVITE message via the call control device A, the registration information stored in the registration information storage unit 37 is referred to, and the INVITE message is sent to the destination according to the registration information. Transferred. The message creation unit 34 is a functional unit that creates a registration message having the telephone number included in the registration message received from the terminal and the address information (IP address, port number, etc.) of the call control device B. Note that the message creation unit 34 may create a registration message to be transmitted by replacing the address information of the terminal with the address information of the call control device B in the registration message received from the terminal. The transmission unit 35 is a functional unit that transmits the registration message created by the message creation unit 34 to the call control device A.

  The call control device B according to the present embodiment can be realized by executing a program corresponding to the processing described in the present embodiment in a computer including a memory and a CPU, or a communication device including a computer configuration. . The program may be stored and distributed in a storage medium such as a portable memory, installed in the computer, or downloaded from a server on the network and installed in the communication device. Further, the processing described in the present embodiment may be realized as a hardware circuit, and the call control device B may be realized by the hardware circuit.

(System operation)
Next, an operation example of the communication system according to the present embodiment will be described with reference to the sequence diagram of FIG. In the following description, the function unit shown in FIG. 4 is also referred to as appropriate. The following operations are performed by the terminal C connected to the call control device B transmitting a registration message to the call control device B, and then the terminal D connected to the call control device A is connected to the terminal C. An example in which a call connection request message (specifically, an INVITE message) is transmitted and a call connection is made is shown. Hereinafter, the telephone number of the terminal C is denoted as telephone number C, the address information of the terminal C is denoted as address information C, and the address information of the call control device B is denoted as address information B. Note that FIG. 5 does not show a response message for the registration message.

  Terminal C transmits a registration message including telephone number C and address information C to call control device B (step 1). In the call control device B, the terminal confirmation unit 32 refers to the terminal information storage unit 36 to check whether the telephone number C included in the received registration message is stored in the terminal information storage unit 36. It is determined whether or not the terminal C is a legitimate terminal allowed to connect to the call control device B (step 2). In this example, it is assumed that the terminal is a valid terminal. If the terminal is not valid, for example, an error is returned and the subsequent processing is not performed.

  Next, the registration processing unit 33 of the call control device B stores the telephone number C and the address information C included in the received registration message in association with each other in the registration information storage unit 37 (step 3). Then, the message creation unit 34 creates a registration message having the telephone number C and the address information B, and transmits the registration message to the call control device A by the transmission unit 35 (step 4). In the call control device A, the telephone number C and the address information B are registered in association with each other based on the normal SIP function.

  Due to the registration message from the terminal C, after registration is performed in the call control device A and the call control device B, a registration message is periodically transmitted from the terminal C. In response to receiving the registration message from the terminal C, the registration information is updated, the registration message is transmitted to the call control device A, and the call control device A updates the registration information. When the call control device B and the call control device A do not receive the registration message for a predetermined period set in the registration message, the registration information registered by the registration message is deleted. For example, if the terminal C moves out of the service area from being connected to the mobile phone network, the registration message cannot be transmitted from the terminal C, the call control device B does not receive the registration message from the terminal C, and The control device A also does not receive the registration message from the call control device B due to the registration message of the terminal C. As a result, the registration information regarding the terminal C is deleted almost simultaneously in the call control device B and the call control device A.

  Further, when an operation such as termination of the call application is performed at the terminal C, a message (Unregister) including a request to delete registration information is transmitted from the terminal C. As in the case of the above registration message, the call control device B that has received this message performs terminal confirmation, and if it is determined to be a valid terminal, deletes the registration information of the terminal C and calls the message. The call control device A also deletes the registration information of the terminal C.

  After step 5 in FIG. 5, when the registration information of terminal C continues, the call connection request in which terminal D sets the destination telephone number as the telephone number C of terminal C A message is transmitted to the call control device A (step 6). Based on the registration information, the call control device A forwards the call connection request message to the address information B corresponding to the telephone number C, and the call connection request message reaches the call control device B having the address information B ( Step 7).

  In the call control device B, based on the registration information, the call connection request message is transferred with the address information C corresponding to the telephone number C as the destination, and the call connection request message reaches the terminal having the address information C (step 8). . Thereafter, a response message is returned (steps 9 to 11). As a result, a call is established between the terminal C and the terminal D, and a call is performed (step 12).

  FIG. 6 shows that after step 5 shown in FIG. 5, the terminal C moves out of service area or the terminal C is turned off, for example, so that transmission of the REGISTER message is interrupted, and the call control device B and the call control device In each of A, the case where the registration information related to the terminal C is deleted is shown.

  After the registration information on terminal C is deleted, call control device A receives a call connection request message from terminal D in which the destination telephone number is set to telephone number C, which is the telephone number of terminal C (step) 21). In this case, the call control device A itself can detect that the address information corresponding to the telephone number C is not registered, and can quickly return an error response (step 22).

  As described above, according to the present embodiment, it is possible to synchronize the registration information in the call control device A such as IP-PBX and the actual state of each terminal under the call control device B. As a result, when the terminal C under the control of the call control device B is out of the communication range, the call control device A that has received the call connection request from the communication network A to the terminal C is not registered in the terminal C in a short time. For example, it is possible to quickly perform call control such as error response transmission and transfer to another terminal set in advance. In addition, since unnecessary messages are not transmitted, communication resources are not wasted.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible within the scope of the claims.

1, 2 Communication network 10, 20 SIP server
NA, NB communication network
A, B Call control device 31 Reception unit 32 Terminal confirmation unit 33 Registration processing unit 34 Message creation unit 35 Transmission unit 36 Terminal information storage unit 37 Registration information storage unit

Claims (4)

Used as the second call control device in the communication system in which the second call control device connected to the second communication network is connected to the first call control device connected to the first communication network. A call control device comprising:
Receiving means for receiving a registration message including a terminal telephone number that is the telephone number of the terminal and terminal address information that is the address information of the terminal from the terminal;
Registration processing means for storing in the registration information storage means the terminal telephone number and the terminal address information in the registration message received by the receiving means;
Message creating means for creating a registration message by replacing the terminal address information in the registration message received by the receiving means with the address information of the call control device;
A call control apparatus comprising: a transmission means for transmitting the registration message created by the message creation means to the first call control apparatus.   The call control device according to claim 1, wherein the first call control device is an IP-PBX functioning as a SIP server, and the call control device is a SIP server. Used as the second call control device in the communication system in which the second call control device connected to the second communication network is connected to the first call control device connected to the first communication network. A registration processing method executed by the call control device,
A receiving step of receiving a registration message including a terminal telephone number that is the telephone number of the terminal and terminal address information that is the address information of the terminal from the terminal;
A registration processing step of storing in the registration information storage means the terminal telephone number and the terminal address information in the registration message received by the receiving step;
A message creating step of creating a registration message in which the terminal address information in the registration message received by the receiving step is replaced with the address information of the call control device;
A registration processing method comprising: a transmission step of transmitting the registration message created in the message creation step to the first call control device. The second call control device in a communication system in which a computer is connected to a first call control device connected to the first communication network and a second call control device connected to the second communication network. A program for causing a computer to function as a call control device used as a computer,
Receiving means for receiving a registration message including a terminal telephone number that is the telephone number of the terminal and terminal address information that is the address information of the terminal from the terminal;
Registration processing means for storing the terminal telephone number and the terminal address information in the registration message received by the receiving means in a registration information storage means;
Message creating means for creating a registration message by replacing the terminal address information in the registration message received by the receiving means with the address information of the call control device;
Transmitting means for transmitting the registration message created by the message creating means to the first call control device;
Program to function as.

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