JP2017192055A - Call control device, call system and program - Google Patents

Abstract

The present invention provides a held group conference call service capable of starting a group conference call based on an incoming call via a communication network that does not notify a callee's identification information to a destination.
A call control apparatus according to the present invention is capable of identifying a terminal transmitted from the terminal when the connection with the terminal via the network is established based on an incoming call from the terminal, and the terminal. It acquires the holding instruction information for instructing the holding of the conference call by the group to which the terminal belongs, and belongs to the group to which the terminal identified by the holding instruction information belongs in response to the holding instruction information being acquired by the acquiring means A terminal that makes a call to each of a plurality of terminals other than the terminal via the network, and that has established a connection via the network based on a call made by the calling means, and via a network based on an incoming call Processing for making a conference call with a terminal with which a connection has been established is performed.
[Selection] Figure 1

Description

  The present invention relates to a call control device, a call system, and a program for providing a conference call service for performing simultaneous calls between a plurality of terminals.

  In Patent Document 1, as a kind of simultaneous multi-party call, an identification number (group special number) of the group and a member belonging to the group are stored in advance in correspondence with each group, and a group telephone number is addressed from a certain telephone terminal. When a call is made, a group member corresponding to the special number is called, and a service called a group call in which a call is started only by the group member is shown. This type of service is sometimes referred to as a hosted group conference call service.

JP 2001-28631 A

  However, in some communication networks such as an analog public switched telephone network, the identification information of the caller is not notified to the called party. When receiving an incoming call via such a communication network, the call control device that provides the hosted group conference call service identifies whether the caller (source) is a member of the hosted group conference call. Cannot provide hosted group conference call service.

  The present invention has been made paying attention to the above circumstances, and the purpose thereof is to be able to start a group conference call based on an incoming call through a communication network that does not notify the callee's identification information to the callee. To provide a call control device, a call system, and a program.

  In order to achieve the above object, according to a first aspect of the present invention, when a connection with the terminal via a network is established based on an incoming call from the terminal, the terminal transmitted from the terminal can be identified. And holding instruction information for instructing holding of a conference call by a group to which the terminal belongs, and is identified by the holding instruction information in response to the acquisition means acquiring the holding instruction information. A call is made to each of a plurality of terminals different from the terminal belonging to the group to which the terminal belongs, and connection via the network is established based on a call made by the calling means. A process for performing a conference call between the established terminal and the terminal that has established a connection via the network based on the incoming call is performed. .

  In the second aspect, the holding instruction information that changes with time is acquired.

  According to the first aspect, it is possible to provide a holding type group conference call service capable of starting a group conference call based on an incoming call via a communication network that does not notify the destination identification information to the destination. .

  According to the second aspect, compared to the case where terminal identification information that does not change with time is used, the hosting group conference call is prevented from being performed by a third party that is not intended to participate in the hosting group conference call. It becomes easy.

The block diagram which shows the principal part structure of the call server which concerns on embodiment of this invention, and the whole structure of the call system provided with this call server. The figure which shows an example of the table with which the telephone call server shown in FIG. 1 is provided. The figure which shows an example of the table with which the telephone call server shown in FIG. 1 is provided. The sequence diagram which shows the flow of the information in the telephone call system shown in FIG. The flowchart which shows the control processing by CPU shown in FIG. The flowchart which shows the control processing by CPU shown in FIG. The figure which shows the modification of the table with which the telephone call server shown in FIG. 1 is provided. The figure which shows the modification of the table with which the telephone call server shown in FIG. 1 is provided.

Embodiments according to the present invention will be described below with reference to the drawings.
(Constitution)
FIG. 1 is a block diagram showing the main configuration of a call server according to an embodiment of the present invention and the overall configuration of a call system including the call server. The call system 1 includes a call server 10, a gateway 20, a plurality of terminals 30A, a plurality of terminals 30B, a local area network 40, and a telephone line network 50. The call server 10, the gateway 20, and the plurality of terminals 30A are connected to the local network 40. The gateway 20 and the plurality of terminals 30B are connected to the telephone line network 50. In the call system 1, under the control of the call server 10, a call between the terminals 30A, that is, a so-called extension call is made possible using a VoIP (voice over Internet protocol) technology. Further, the call system 1 enables a call between the terminal 30A and the terminal 30B, that is, a so-called outside line call, through the gateway 20. For the control in the local network 40 in the extension call and the outside call, SIP (Session Initiation Protocol) is used as a protocol for performing call control, and RTP (Real-time Transport Protocol) and RTCP (Real-time) are used as protocols for transmitting and receiving voice. Transport Control Protocol) is used.

  The call server 10 includes a central processing unit (CPU) 11, a main memory 12, an auxiliary storage device 13, a communication interface 14, and a bus 15. As the call server 10, an IP telephony server is typically used. The call server 10 is an example of a call control device. In another example, the call server 10 and the gateway 20 connected via the local network 40 constitute a call control device.

  The CPU 11 corresponds to a central part of a computer that performs processing and control necessary for the operation of the call server 10. The CPU 11 controls each unit to implement various functions of the call server 10 based on programs such as an operating system and application software stored in the main memory 12.

  The main memory 12 corresponds to the main memory portion of the computer. The main memory 12 stores programs such as the operating system and application software. The main memory 12 stores data that the CPU 11 refers to when performing various processes. Further, the main memory 12 is used as a so-called work area that stores data temporarily used when the CPU 11 performs various processes.

  The auxiliary storage device 13 corresponds to the auxiliary storage portion of the computer. The auxiliary storage device 13 is, for example, an EEPROM (electrically erasable programmable read-only memory), an HDD (hard disc drive), or an SSD (solid state drive). The auxiliary storage device 13 stores data used when the CPU 11 performs various processes or data generated by the processes in the CPU 11. The auxiliary storage device 13 may store a program such as the above operating system or application. The auxiliary storage device 13 also stores a conference call database (hereinafter referred to as conference call DB) 131.

The conference call DB 131 manages information for each group in association with a unique group ID (identifier) assigned to each of a plurality of groups for a hosted group conference call. 2 and 3 show examples of the terminal table T1 and the group table T2 included in the conference call DB 131. FIG.
The terminal table T1 registers the terminals 30A and 30B in each group by associating terminal numbers for specifying the terminals 30A and 30B participating in the held group conference call with the group ID. The terminal table T1 includes, as terminal numbers, extension numbers assigned to the terminal 30A by the local network 40 and telephone numbers assigned by the telephone line network 50 to the line to which the terminal 30B is connected. The four-digit numbers such as “0112” and “0270” shown in FIG. 2 are extension numbers. The 10-digit or 11-digit numbers such as “03XXXXXXX” and “090XXXXXXX” shown in FIG. 2 are telephone numbers.
The group table T2 associates, for each group, a special number (hereinafter referred to as “held special number”) determined to instruct the holding of the held group conference call related to the group with the group ID.

  The program stored in the main memory 12 or the auxiliary storage device 13 includes a control program described regarding control processing described later. As an example, the call server 10 is transferred to the user with the control program stored in the main memory 12 or the auxiliary storage device 13. However, the call server 10 may be transferred to the user without the control program being stored in the main memory 12 or the auxiliary storage device 13. Then, the control program separately transferred to the user may be written into the main memory 12 or the auxiliary storage device 13 under the operation of the user or a service person. The transfer of the control program at this time can be realized by recording on a removable recording medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory, or by downloading via a network.

  The communication interface 14 is an interface for the call server 10 to communicate via the local network 40.

The gateway 20 enables mutual communication between the local network 40 and the telephone line network 50 by converting the protocols to each other. That is, the gateway 20 sends a signal transmitted through the telephone line network 50 using a protocol applied to the telephone line network 50 to the local network 40 using a protocol applied to the local network 40. Conversely, the gateway 20 sends a signal transmitted through the local network 40 to the telephone line network 50.
Through the gateway 20, communication between the call server 10 or the terminal 30A and the terminal 30B becomes possible. Thus, the terminal 30A can make a call with the terminal 30B via the telephone line network 50, that is, an outside line call. In FIG. 1, the gateway 20 is shown as an independent device, but the call server 10 may be configured to have the function of the gateway 20.

The terminal 30 </ b> A has a voice call function via the local network 40. An IP telephone is typically used as the terminal 30A. The terminal 30 </ b> A may be configured by a combination of an analog telephone and a device such as a VoIP adapter for connecting the analog telephone to the local network 40.
The terminal 30B has a voice call function via the telephone line network 50. An analog telephone is typically used as the terminal 30B. The terminal 30 </ b> B has a function of sending a push signal such as a DTMF signal (dual tone multi frequency) to the telephone network 50. Note that the terminal 30B may be connected to the telephone line network 50 via PBX (private branch exchange) or the like.
The terminals 30A and 30B may be various types such as a fixed telephone type connected to the local network 40 or the telephone line network 50 via a wired line or a mobile phone type connected to the local network 40 or the telephone line network 50 via a wireless line. Can be used. The terminals 30A and 30B may be computers such as a desktop PC (personal computer), a notebook PC, or a tablet PC in which software for realizing a voice call function is installed. In FIG. 1, only two terminals 30A and 30B are shown, but more terminals 30A and 30B are typically connected to the local network 40 or the telephone line network 50, respectively.

  The premises network 40 is typically an intranet constructed in a premises in units of companies, organizations, groups, buildings, or facilities.

  The telephone line network 50 is a communication network including a public switched telephone network (PSTN), a mobile communication network, a dedicated line, or other telephone lines.

(Operation)
Hereinafter, the operation of the call system 1 will be described with reference to FIGS. Note that the content of the processing described below is an example, and various processing that can obtain the same result can be used as appropriate.

  First, the flow of information in the call system 1 when the terminal 30B whose source number is not notified requests holding of a held group conference call will be described with reference to FIG. Note that a terminal requesting to hold a held group conference call is referred to as a holding terminal. FIG. 4 is a sequence diagram showing a flow of information in the call system 1. Note that FIG. 4 does not cover the information flow in the call system 1, and there may be an information flow (not shown).

When an operator of the terminal 30B wants to perform a held group conference call, the operator of the terminal 30B operates the terminal 30B to set a representative number assigned by the telephone line network 50 to a line connecting the gateway 20 and the telephone line network 50. input.
In step S <b> 1, the terminal 30 </ b> B sends a push signal representing the input representative number to the telephone line network 50.

  In step S2, the telephone line network 50 transmits a calling signal to the line to which the representative number represented by the push signal is assigned, that is, to the gateway 20 in response to receiving the push signal transmitted from the terminal 30B. This processing is performed by an exchange included in the public switched telephone network as an example. In the above description, the representative number is used. However, the telephone number assigned by the telephone line network 50 to the line connecting the gateway 20 and the telephone line network 50 may not be a representative number.

  In step S <b> 3, the gateway 20 sends a response signal to the telephone line network 50 as a reply to the calling signal transmitted from the telephone line network 50.

  In step S4, the telephone line network 50 forms a communication path between the terminal 30B and the gateway 20 in response to receiving the response signal sent from the gateway 20. Thereby, the terminal 30B and the gateway 20 are connected via the telephone line network 50.

  In step S5, the gateway 20 transmits an audio signal representing a second dial tone to the terminal 30B in order to allow the operator of the terminal 30B to input the extension number. Or you may transmit to the terminal 30B the audio | voice signal showing the guidance audio | voice for making the operator of the terminal 30B input an extension number. The voice signal transmitted from the gateway 20 reaches the terminal 30B via the telephone line network 50. When the terminal 30B receives the voice signal, the terminal 30B emits a second dial tone or guidance voice indicated by the voice signal as a sound through a built-in speaker or the like.

When the second dial tone or the guidance voice is emitted from the terminal 30B, the operator of the terminal 30B operates the terminal 30B to input a number including the host special number and the terminal number of the terminal 30B. As an example, enter "9001 # 03XXXXXXXX". Of these, “9001” is the special number for the event. “03XXXXXXXX” is the terminal number of the terminal 30B. Note that “#” is a separator for easily separating the host special number and the terminal number of the terminal 30B.
In step S6, the terminal 30B sends the number input in response to the above operation by the operator of the terminal 30B to the telephone line network 50 as a push signal. The push signal transmitted from the terminal 30B reaches the gateway 20 via the telephone line network 50. In step S6, the terminal 30B operates as a transmission unit.

  In step S 7, the gateway 20 generates a connection request (INVITE) for establishing a communication session with the call server 10 in response to receiving the push signal transmitted from the telephone line network 50. Is transmitted to the call server 10. At this time, the gateway 20 includes a predetermined character string indicating that the incoming call is from the outside line in the connection request. That is, for example, the gateway 20 sets the From header field of the connection request to “from: sip: 1000@192.168.0.40”. Of these, the character string “1000” is predetermined information indicating that the call is from an outside line. The character string “192.168.0.40” is an example of the local IP address of the gateway 20. By doing as described above, the call server 10 that has received this connection request knows that the connection request is caused by an incoming call from an outside line. When the telephone number of the caller is notified from the telephone line network 50, the gateway 20 includes the telephone number in the connection request.

  Furthermore, the gateway 20 includes “9001 # 03XXXXXXXX”, which is a number transmitted as a push signal from the terminal 30B, in the connection request. That is, the gateway 20 sets the to header field of the information notification as “to: sip: 9001#03XXXXXXXX@192.168.0.30” as an example. Among these, the character string “192.168.0.30” is an example of the local IP address of the call server 10. As described above, the call server 10 that has received this connection request can acquire the number transmitted as a push signal from the terminal 30B. In addition, the call server 10 can identify the holding special number and the terminal number by separating “9001 # 03XXXXXXXX” into “9001” and “03XXXXXXXX”.

  In step S <b> 8, the call server 10 generates a success response (OK) indicating that the connection is permitted in response to receiving the connection request transmitted from the gateway 20, and transmits this success response to the gateway 20. .

  In step S <b> 9, the gateway 20 transmits an acknowledgment message (ACK) to the call server 10 in response to receiving the success response transmitted from the call server 10. As a result, a communication session between the gateway 20 and the call server 10 via the local network 40 is established.

After transmitting a success response to the gateway 20, the call server 10 refers to the conference call DB 131, and among the terminals 30A and 30B registered in the group whose holding special number is 9001, all the terminals 30A and 30A except the holding terminal Calls to 30B all at once. FIG. 4 shows a case where a call is made to one terminal 30A and one terminal 30B as an example. In the following description, steps S10 to S13 and S14 to S20 are described as being performed sequentially, but in actuality, they are processed in parallel.
In step S10, the call server 10 generates a connection request (INVITE) for establishing a conference call session, and transmits the connection request to the terminal 30A.

  In step S <b> 11, the terminal 30 </ b> A generates an incoming response (Ringing) in response to receiving the connection request, and transmits it to the call server 10. In addition, the terminal 30A emits a ringing tone in response to receiving the connection request, and notifies the operator of the terminal 30A of the incoming call. When responding to an incoming call, the operator of terminal 30A places terminal 30A off-hook.

  In step S <b> 12, the terminal 30 </ b> A generates a success response (OK) in response to being off-hook, and transmits this success response to the call server 10.

  In step S13, the call server 10 transmits an acknowledgment message (ACK) to the terminal 30A that has transmitted the success response in response to receiving the success response transmitted from the terminal 30A. Thereby, a communication session for a conference call between the terminal 30A and the call server 10 is established. Through the communication session, the call server 10 and the terminal 30A are in a state where they can talk to each other.

  In step S <b> 14, the call server 10 generates a connection request (INVITE) including the terminal number of the terminal 30 </ b> B, and transmits this connection request to the gateway 20.

  In step S <b> 15, the gateway 20 sends a push signal representing the terminal number included in the connection request to the telephone line network 50 in response to receiving the connection request transmitted from the call server 10.

  In step S16, in response to receiving the push signal sent from the gateway 20, the telephone line network 50 transmits a calling signal to the line specified by the number represented by the push signal. The call signal is sent to the new terminal 30B connected to the line via the line. The new terminal 30B that has received the calling signal emits a ringing tone. In response, the operator of the new terminal 30B takes the new terminal 30B off-hook when responding to an incoming call.

  In step S17, the new terminal 30B sends a response signal to the telephone network 50 in response to being off-hook.

  In step S18, the telephone network 50 forms a communication path between the new terminal 30B and the gateway 20 in response to receiving the response signal transmitted from the new terminal 30B. As a result, the new terminal 30 </ b> B and the gateway 20 are connected via the telephone line network 50.

  In step S19, the gateway 20 generates a success response (OK) indicating that the connection is permitted in response to the connection between the new terminal 30B and the gateway 20, and sends the success response to the call server 10. Send.

  In step S <b> 20, the call server 10 transmits an acknowledgment message (ACK) to the gateway 20 in response to receiving the success response transmitted from the gateway 20. As a result, a new communication session between the call server 10 and the gateway 20 is established. With this communication session and the communication path formed as described above via the telephone line network 50, the call server 10 and the new terminal 30B are in a state where they can talk to each other.

  In step S21, a conference call via the call server 10 is held between the terminal 30A and the two terminals 30B. Specifically, the call server 10 synthesizes the transmission voices sent from the terminal 30B on the transmission side and the terminal 30B on the reception side to generate a reception voice, and sends the reception voice to the terminal 30A. Further, the call server 10 synthesizes the transmission voices respectively transmitted from the terminal 30B on the transmission side and the terminal 30A to generate a reception voice, and sends the reception voice to the terminal 30B on the reception side. Furthermore, the call server 10 synthesizes the transmission voices respectively transmitted from the terminal 30B on the receiving side and the terminal 30A to generate a reception voice, and sends the reception voice to the terminal 30B on the transmission side. These various voices are transmitted between each communication session established between the call server 10 and the terminal 30A, a communication session established between the call server 10 and the gateway 20, and between the terminal 30B and the call server 10. The data is transmitted through a communication path formed via the line network 50.

  Next, a more detailed operation of the call server 10 will be described with reference to FIGS. 5 and 6 are flowcharts of control processing by the CPU 11 of the call server 10. The CPU 11 executes this control process based on the control program stored in the main memory 12 and the auxiliary storage device 13.

  In step ST <b> 1, the CPU 11 waits for the communication interface 14 to receive a connection request (INVITE) to the call server 10. This connection request corresponds to that transmitted by the gateway 20 in step S7 in FIG. If the connection request is received, the CPU 11 determines Yes in step ST1, and proceeds to step ST2.

  In step ST2, the CPU 11 acquires the contents described in the From header field and the to header field, which are branch information of the subsequent steps, from the connection request received in step ST1. Information such as “9001 # 03XXXXXXXX” included in the to header field corresponds to holding instruction information for identifying a terminal and instructing holding of a conference call by a group to which the terminal belongs. Therefore, in this process, the computer having the CPU 11 as the center operates as an acquisition unit.

  In step ST3, the CPU 11 confirms whether or not it indicates an incoming call from an outside line from the description content of the From header field acquired in step ST2. That is, the CPU 11 checks whether or not the connection request includes the above-described character string indicating that the call is from an outside line. If the character string is included, the caller is an outside line. In this case, the CPU 11 determines Yes and proceeds to step ST4. If the connection request does not include a character string indicating that the call is from an outside line, the CPU 11 determines No and shifts to other processing according to the connection request. A known process can be applied to an incoming call from an extension.

  In step ST4, the CPU 11 checks whether or not the special number included in the to header field acquired in step ST2 is included in the holding special number of the group table T2. If the host special number is included, the CPU 11 determines Yes in step ST4 and proceeds to step ST5. Note that the operator of the terminal 30B who has heard the second dial tone or the guidance voice emitted from the terminal 30B can input a number other than the host special number. For example, if the operator of the terminal 30B wants to make a call with one terminal 30A, the operator inputs the extension number assigned to the terminal 30A. Alternatively, if a service other than the held group conference call service provided by the call server 10 is to be used, a special number assigned to the service is input. In these cases, the CPU 11 determines No in step ST4, and performs processing according to the number input as described above and transmitted as a push signal from the terminal 30B.

  In step ST <b> 5, the CPU 11 refers to the group table T <b> 2 and specifies the group ID from the host special number. For example, the CPU 11 specifies “10001” as the group ID if the group table T2 has the contents as shown in FIG. 3 and the hosting special number “9001”.

  In step ST6, the CPU 11 confirms whether or not the telephone number of the caller is included in the description content of the to header field acquired in step ST2. If the telephone number of the caller is not included in the description content of the to header field, the CPU 11 determines No and proceeds to step ST7. If the caller's telephone number is included in the description content of the to header field, the CPU 11 determines Yes and performs processing according to the description content. For example, if the caller's telephone number is included in the to header field, the CPU 11 performs a known process for providing a hosted group conference call service.

  In step ST7, the CPU 11 refers to the terminal table T1 to determine whether the terminal number is included in the description content of the to header field acquired in step ST2 and whether the terminal number is associated with the group ID specified in step ST5. And confirm. In other words, it is confirmed whether or not the terminal table T1 has a record including the group ID and the terminal number. If the terminal number is included and the terminal number is associated, CPU 11 determines Yes and proceeds to step ST8.

  In step ST8, the CPU 11 generates a success response (OK) indicating that the connection request has been successfully received, and instructs the communication interface 14 to transmit this success response to the connection request transmission source. This success response corresponds to that transmitted by the call server 10 in step S8 in FIG.

  In step ST <b> 9, the CPU 11 waits for the communication interface 14 to receive the confirmation message (ACK) transmitted from the connection request transmission source. If the confirmation message is received, the CPU 11 determines Yes in step ST9 and proceeds to step ST10 in FIG.

In step ST10 to step ST13, the CPU 11 performs in parallel with respect to each terminal excluding the host terminal among the terminals 30A and 30B specified by the terminal number associated with the group ID specified in step ST5 in the terminal table T1. Process. Since the host terminal is already in a state where a call with the conference server is possible, the process of step ST13 is performed in parallel with the process of step ST10 to step ST13 for the other terminals without performing the process of steps ST10 to ST12. Do it. Although FIG. 6 shows that processing for three terminals including processing for the host terminal is performed in parallel, the processing is actually performed in parallel by the number of terminals. In the following description of step ST10 to step ST13, processing for one terminal 30A or 30B will be described as a representative.
In step ST10, the CPU 11 refers to the terminal table T1 and makes a call to the terminal 30A or 30B specified by the terminal number associated with the group ID specified in step ST5. That is, the CPU 11 generates a connection request (INVITE) and instructs the communication interface 14 to transmit this connection request to the terminal 30A or the gateway 20. This connection request corresponds to that transmitted by the call server 10 in step S10 or S14 in FIG.
As a result, the communication interface 14 makes a call to each of the plurality of terminals 30A and 30B, which belong to the group to which the host terminal belongs, under the control of the CPU 11 and which are different from the host terminal. Alternatively, the CPU 11 may instruct the communication interface 14 to call each terminal 30A and 30B sequentially. In the process of making a call to each of the terminals 30A and 30B, the CPU 11 and the communication interface 14 operate as a calling unit.

  In step ST11, the CPU 11 waits for the success response (OK) transmitted from the terminal 30A or the gateway 20 that is the connection request transmission destination to be received by the communication interface. In FIG. 4, this success response corresponds to the one transmitted by the terminal 30A in step S12 or the one transmitted by the gateway 20 in step S19. If the success response is received, the CPU 11 determines Yes in step ST11 and proceeds to step ST12. If the success response is not received for a certain period of time, the CPU 11 stops the process of step ST11 and further skips the processes of step ST12 and step ST13.

  In step ST12, the CPU 11 instructs the communication interface 14 to transmit a confirmation message (ACK) to the transmission source of the success response. As a result, a communication session for a conference call between the terminal 30A or the gateway 20 that is the source of the success response and the call server 10 is established. This confirmation message corresponds to the message transmitted by the call server 10 in step S13 or step S20 in FIG.

In step ST13, the CPU 11 performs conference call processing. As the conference call process, a well-known process can be applied, and the description thereof will be omitted. The CPU 11 ends the process of step ST13 in response to receiving a request for leaving the conference call from the terminal 30A or 30B. In step ST13, the computer having the CPU 11 as the center operates as processing means.
CPU11 progresses to step ST14 according to having complete | finished or skipped the process of step ST13 with respect to the terminals 30A and 30B currently processed in parallel.

  In step ST14, the CPU 11 performs a conference end process. That is, the CPU 11 confirms that the connection with each of the terminals 30A and 30B processed in parallel is disconnected. When there is a terminal that is not disconnected, the CPU 11 disconnects the connection with the terminal. After the process of step ST14, the CPU 11 returns to step ST1.

On the other hand, if the terminal number is not included in the to header field acquired in step ST2 or the terminal number included in the to header field is not associated with the group ID specified in step ST5, the CPU 11 in FIG. In Step ST7, No is determined and the process proceeds to Step ST15.
In step ST15, the CPU 11 generates a failure response (4xx) indicating that processing according to the content indicated by the connection request cannot be performed, and instructs the communication interface 14 to transmit this failure response to the connection request transmission source.

  In step ST16, the CPU 11 performs a process of disconnecting the connection with the terminal 30B that has transmitted the connection request. After the process of step ST16, the CPU 11 returns to step ST1.

(effect)
As described above, in the embodiment, the call server 10 can identify the terminal 30B by the number transmitted from the terminal 30B that is the hosting terminal. Accordingly, since the call server 10 can identify the source terminal even when the telephone line network 50 does not notify the source identification information, such as when the host terminal is an external terminal, A group conference call can be started.

  Further, as described above, in the embodiment, the call server 10 can identify not only the host terminal but also a group that is a target of the group meeting to be started from the number transmitted from the host terminal. The call server 10 executes a process for holding a group meeting only when the host terminal belongs to a group that is a target of the group meeting to be started. Therefore, if the operator of the host terminal does not properly input the host special number and the terminal number, the process for holding the group meeting will not be executed. It can be prevented from being held.

  The embodiment described above can be modified as follows.

In the embodiment, as shown in the terminal table T1, the telephone number of the terminal 30B is used as the terminal number of the terminal 30B. However, a number other than the telephone number of the terminal 30B may be used as the terminal number of the terminal 30B. For example, a terminal table T3 as shown in FIG. 7 is used instead of the terminal table T1. FIG. 7 is a diagram illustrating an example of the terminal table T3 included in the conference call DB 131. The terminal table T3 includes a unique number such as “93664”, “13300”, or “08225” as a terminal number of the terminal 30B in association with each telephone number. In this case, when the second dial tone or the guidance voice is emitted from the terminal 30B, the operator of the terminal 30B determines that the terminal number is input after the host special number in using the communication system. That is, the operator of the terminal 30B inputs “9001 # 93664”. In step ST7, the CPU 11 determines whether the terminal number is included in the description content of the to header field acquired in step ST2 and whether the terminal number is associated with the group ID specified in step ST5. Confirm with reference to table T3. In step ST10, the CPU 11 makes a call to the telephone number associated with the group ID specified in step ST5 in the terminal table T3.
Now, a person who requests to hold a holding type group conference call needs to know the holding special number and the terminal number. Among these, as shown in the terminal table T1 of FIG. 2, the terminal number is a telephone number for the terminal 30B in the embodiment. The telephone number is not a number dedicated to the hosting group conference call but a number used when making a call to the terminal 30B. For this reason, the telephone number is usually information that can be known even by a person unrelated to the held group conference call. On the other hand, when the terminal number set for the holding type group conference call is used as a number different from the telephone number as described above, the terminal number is not disclosed except for the parties related to the group conference. be able to. Therefore, it is easier to prevent a hosted group conference call from being made due to a request from a third party who is not intended to participate in the hosted group conference call compared to the case where a telephone number is used as a terminal number.

  Further, the terminal number of the terminal 30B in the terminal table T3 may be a number that changes with time. In this case, the operator of the terminal 30B has in advance a hardware token that displays a terminal number that changes over time. In this way, the hosted group conference call is performed by a third party who is not intended to participate in the hosted group conference call, rather than simply using a number different from the phone number as the terminal number. It becomes easy to prevent that.

  The terminal number that changes over time may be one that can be derived by the operator of the terminal 30B from the current time or date under a certain rule. In this case, the operator of the terminal 30B can derive the terminal number by knowing the law in advance. Further, the operator of the terminal 30B can derive the terminal number by holding in advance a storage medium in which the rule is stored. For example, a rule that the last four digits of the terminal number are the date of the day is determined in advance. Further, for example, a table in which numbers that change with time are associated with time or date is held in advance. By using this table, the operator of the terminal 30B can know the number that changes over time. In this way, it is possible to use a number that changes over time without a device such as a hardware talk.

  In the embodiment, the number including the host special number and the phone number of the terminal 30B is used. Instead of the number, one number that can identify the host special number and the phone number of the terminal 30B is used. Also good. In this case, a terminal table T4 as shown in FIG. 8 is used as an example instead of the terminal table T1. The terminal table T4 includes a unique individual special number for the terminal 30B in addition to the telephone number in association with the group ID and the terminal number. The terminal table T4 can include a plurality of the same telephone numbers in association with different group IDs. Individual held special numbers are different from each other if the combination of the group ID and the telephone number is different. Note that the operator of the terminal 30B needs to know the special event special number in advance. When it is desired to hold a hosted group conference call from the terminal 30B, after the second dial tone or guidance voice is emitted from the terminal 30B, the operator of the terminal 30B inputs the individual host special number. As a result, the individual host special number is included in the to header field of the connection request to the call server 10. In step ST4, the CPU 11 confirms whether or not the individual host special number included in the description content of the to header field acquired in step ST2 is included in the terminal table T4. In step ST5, the CPU 11 specifies the group ID associated with the individual host special number in the terminal table T4. If the CPU 11 determines No in step ST6, it proceeds to step ST8 without performing step ST7. Therefore, CPU11 does not perform step ST15 and step ST16. In this case, the group table T2 is not necessary.

  In the embodiment, the number is input each time the operator of the terminal 30B requests to hold a holding type group conference call. However, the number may be stored in a storage device provided in the terminal 30B. In this case, the operator of the terminal 30B performs a predetermined operation for transmitting the stored number to the terminal 30B as a push signal. In response to this operation, the terminal 30B transmits the number as a push signal to the telephone line network 50.

  In the embodiment, the holding special number is set for each group ID. However, a common holding special number may be used without setting the holding special number for each group ID. In this case, the CPU 11 specifies the terminal number of the host terminal from the number transmitted from the host terminal, and specifies the group ID from the specified terminal number. Then, the CPU 11 makes a call to the terminals 30A and 30B other than the host terminal associated with the group ID.

  In the embodiment, after transmitting the failure response in step ST15, the CPU 11 disconnects the connection with the terminal 30B that transmitted the connection request. However, the CPU 11 may instruct the communication interface 14 to transmit, to the terminal 30B, an audio signal indicating that an appropriate terminal number has not been input and that the voice is provided to guide the user to dial the number again. .

  In the embodiment, the gateway 20 transmits an audio signal to the terminal 30B in step S5. However, the call server 10 may transmit an audio signal to the terminal 30B. In this case, the gateway 20 establishes a connection with the call server 10 in response to receiving the call signal transmitted from the telephone line network 50 in step S2. A well-known method using SIP can be used for establishing the connection. Thereby, after the connection between the gateway 20 and the terminal 30 </ b> B is established in step S <b> 4, the call server 10 can transmit an audio signal to the terminal 30 </ b> B via the gateway 20.

  In the embodiment, SIP is used as a protocol for performing call control, but H.264 recommended by ITU-T (International Telecommunication Union Telecommunication Standardization Sector). A mode using other protocols such as a protocol defined in H.323 may be used.

  In addition, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

DESCRIPTION OF SYMBOLS 1 ... Call system, 11 ... CPU, 12 ... Main memory, 13 ... Auxiliary storage device, 14 ... Communication interface, 15 ... Bus, 20 ... Gateway, 30A, 30B ... Terminal, 40 ... Private network, 50 ... Telephone line network, 131 ... Conference call DB, T1, T3 ... Terminal table, T2 ... Group table.

Claims (4)

When a connection with the terminal via the network is established based on an incoming call from the terminal, the terminal is identifiable and the conference call is instructed by the group to which the terminal belongs. Acquisition means for acquiring holding instruction information for
In response to the acquisition instruction information being acquired by the acquisition means, each of a plurality of terminals different from the terminal belonging to the group to which the terminal identified by the holding instruction information belongs A calling means for calling through a network;
In order to cause a conference call to be established between the terminal that has established a connection via the network based on a call made by the calling means and the terminal that has established a connection via the network based on the incoming call. Processing means for performing the process;
A call control device comprising: The acquisition means acquires the holding instruction information that changes with time,
The call control device according to claim 1. A call system that enables communication between a plurality of terminals and a call control device via a network,
At least one of the plurality of terminals is
When calling the call control device and establishing a connection with the call control device via the network, the terminal can be identified and instructing the holding of the conference call by the group to which the terminal belongs Including transmission means for transmitting the holding instruction information of
The call control device includes:
Obtaining means for obtaining the holding instruction information transmitted from the terminal;
In response to the acquisition instruction information being acquired by the acquisition means, each of a plurality of terminals different from the terminal belonging to the group to which the terminal identified by the holding instruction information belongs A calling means for calling through a network;
Processing means for performing a process for making a conference call between the terminal established through the network based on a call made by the calling means and the terminal that has transmitted the holding instruction information;
A call system comprising:   The program which makes the computer with which the said call control apparatus performs the process by each said means with which the call control apparatus of Claim 1 or Claim 2 is equipped is performed.