JP2014078887A - Communication control device, communication control method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cancel congestion state at an early stage to stabilize call service even if the congestion state occurs.SOLUTION: In a subscriber accommodation server 13, an instruction section 23 shifts a connection state of a communication terminal of a transmission source of a connection request to a standby state, a communication control section 22 determines whether a free line exists or not. When the free line exists, a first connection section 24 makes a connection with a communication terminal of a connection destination subscriber, and when the free line does not exist, a registration section 25 registers in a waiting list subscriber information of the connection destination and subscriber information of the connection source included in the connection request, a forced disconnection section 26 monitors a call in the connection state and forcibly disconnects the call which satisfies predetermined conditions, and a second connection section 27 allocates a new call connection to a free line generated by disconnection and makes a connection with the communication terminal which is registered in the waiting list.

Description

  The present invention relates to a communication control device, a communication control method, and a program.

  In a communication system, a connection request (traffic) to a server varies depending on external factors such as a place where a user uses a communication terminal and a use time zone. For example, when an event such as a fireworks display, a sporting game, or a concert is held, a connection request several times to several tens of times may occur. Under such circumstances, a large number of connection requests are rushed to the server, so that a congestion state may occur and a stable call service may not be provided.

  In order to prevent such a congestion state, a technique is known in which priority control is performed on a connection request from a user to reduce the load on the communication system and to reduce the connection request again. (For example, refer to Patent Document 1). In the technique disclosed in Patent Document 1, as a means for securing a connection at the time of congestion, a time zone that can be preferentially connected is issued in advance for each communication terminal of the user, and the priority connection time zone that is issued in advance. Adopts a method of requesting connection from the user's communication terminal. As a result, there is an effect of prompting the user in advance for a connection request in the priority connection time zone, so that connection requests concentrated in a short time can be distributed. As a result, it is possible to reduce connection requests from users who cannot be connected, and thus it is possible to reduce the load on the communication system.

JP 2004-120136 A

  However, in the priority control disclosed in Patent Document 1, when a large number of sudden connection requests occur (for example, when a disaster occurs), the priority is issued because it is assumed that the priority is acquired in advance. Most callers who are not connected cannot connect. For this reason, a caller who cannot connect to a connection destination subscriber repeatedly makes a connection request in a short time until the connection can be established, and a large number of connection requests are rushed to the server, resulting in a congestion state for a long time. Will occur. In addition, in the priority control disclosed in Patent Document 1, once a congestion state is reached, it can be connected only within a range that does not exceed the maximum number of priority issues per unit time. The call service cannot be stabilized at an early stage.

  Therefore, the present invention solves the above-described problem, that is, a communication control apparatus and communication that can stabilize a call service by quickly eliminating the congestion state even when the congestion state occurs It is an object to provide a control method and a program.

  In order to solve the above-described problem, one aspect of the present invention relates to a communication control device. That is, when a call connection request transmitted to a communication terminal of a subscriber accommodated in a subordinate is received from a communication terminal accommodated in another communication terminal of the own device or another communication control device, the communication of the subscriber In a communication control apparatus for executing a call connection to a terminal, in order to connect to a communication terminal of a connection destination subscriber included in the call connection request, means for notifying a communication terminal that has transmitted a call connection request of a connection waiting state Determining means for determining whether or not there is a necessary free line; and a first means for connecting to the communication terminal of the connection destination subscriber included in the call connection request when the determining means determines that there is a free line. A connection means, a registration means for registering the connection source subscriber information and the connection destination subscriber information included in the call connection request in the idle waiting list when it is determined by the determination means that there is no available line; Call As a result, forcible disconnection means for forcibly disconnecting calls that meet the specified conditions, and when the call is forcibly disconnected by the forcible disconnection means, it is registered in the idle waiting list in the free line generated by the disconnection. And a second connection means for connecting to the communication terminal based on the call connection request being made.

  In addition to the above-described configuration, the communication control device of the present invention is configured so that the predetermined condition for the forced disconnection means to disconnect the call connection is that the connection destination is determined when a predetermined time has elapsed since the connection between the communication terminals was established. When the connection state of the communication terminal of the subscriber is busy for a certain period of time, it can be at least one of cases where there is no response from the communication terminal of the connection destination subscriber.

  One aspect of the present invention relates to a communication control method. That is, when a call connection request transmitted to a communication terminal of a subscriber accommodated in a subordinate is received from a communication terminal accommodated in another communication terminal of the own device or another communication control device, the communication of the subscriber In a communication control method for executing call connection to a terminal, a step of notifying a communication terminal that has transmitted a call connection request of a connection waiting state, and connection to a communication terminal of a connection destination subscriber included in the call connection request A determination step for determining whether or not there is a necessary free line; and a first step for connecting to the communication terminal of the connection destination subscriber included in the call connection request when the determination step determines that there is a free line. A registration step for registering the connection source subscriber information and the connection destination subscriber information included in the call connection request in the idle waiting list when it is determined that there is no idle line in the connection step and the determination step. And when a call that meets a certain condition is forcibly disconnected, and when the call is forcibly disconnected by the forcible disconnection step And a second connection step of connecting to the communication terminal based on the call connection request registered in the idle waiting list in the idle line.

  Furthermore, one aspect of the present invention relates to a program. That is, when a call connection request transmitted to the subscriber's communication terminal accommodated under the subordinate is received from another communication control device, the computer that performs the call connection to the subscriber's communication terminal transmits the call connection request. A means for notifying the communication terminal of the connection waiting state, a determination means for determining whether or not there is a free line necessary for connection to the communication terminal of the connection destination subscriber included in the call connection request, and a determination means When it is determined that there is no idle line, the first connection means for connecting to the communication terminal of the connection destination subscriber included in the call connection request when it is determined that there is an idle line, Registration means for registering connection source subscriber information and connection destination subscriber information included in the connection request in the idle waiting list, monitoring a call in a connected state, and forcibly disconnecting a call that meets a predetermined condition Strong And a second connection for connecting to the communication terminal based on the call connection request registered in the idle waiting list in the idle line generated by the disconnection when the call is forcibly disconnected by the forcible disconnecting means. It is a program for functioning as means.

  According to the present invention, it is possible to provide a communication control device, a communication control method, and a program that can stabilize a call service by eliminating the congestion state at an early stage even when a congestion state occurs. it can.

1 is a diagram showing a communication system 1 including a communication control device according to an embodiment of the present invention. It is a block diagram which shows the structure of the function of the subscriber accommodation server 13 shown in FIG. It is a flowchart which shows the communication control process which the subscriber accommodation server 13 shown in FIG. 1 performs. It is a figure which shows the connection sequence at the time of implement | achieving the other communication control processing which the subscriber accommodation server 13 shown in FIG. 1 performs by SIP (Session Initiation Protocol). It is a block diagram which shows the structural example of the hardware of a computer.

  Hereinafter, a communication control apparatus according to an embodiment of the present invention will be described with reference to FIGS. Note that the communication control method and program according to the embodiment of the present invention will be described by taking the operation of the communication control device and the program installed in the communication control device as an example.

  First, the configuration of a communication system 1 including a communication control device according to an embodiment of the present invention will be described. FIG. 1 is a diagram showing a communication system 1 including a communication control apparatus according to an embodiment of the present invention. The communication system 1 includes subscriber accommodation servers 11a, 11b, and 11c, a relay server 12, a subscriber accommodation server 13, and a sound source server 14. In this embodiment, the subscriber accommodation server 13 is set to correspond to a function (described later) provided in the communication control device of the claims, and the subscriber accommodation servers 11a, 11b, and 11c corresponding to other communication control devices are set. A call connection request to a communication terminal (not shown) accommodated under its own is received from a communication terminal (not shown) accommodated under the subordinate and connected to the corresponding communication terminal. However, it is also possible to configure the subscriber accommodation servers 11a, 11b, and 11c so as to perform the functions corresponding to the functions (to be described later) provided in the claimed communication control device so that the roles of the subscriber accommodation servers 13 are reversed. It is. In the following description, the subscriber accommodation servers 11a, 11b, and 11c may be simply referred to as the subscriber accommodation server 11 when it is not necessary to distinguish between them.

  The subscriber accommodation server 11 manages service contract information and call state management of communication terminals of all subscribers accommodated under the subscriber accommodation server 11. And the subscriber accommodation server 11 determines the subscriber accommodation server 11 used as the transmission destination of the call signal transmitted from the communication terminal accommodated in subordinates, or is directed to the subordinate communication terminal from other communication terminals. Then, call control such as routing processing for transferring the call signal, response signal, etc. (call control signal) transmitted is performed. The subscriber's communication terminal referred to here is, for example, a stationary telephone set installed in an office or the like. The telephone can generate a call signal (a kind of call control signal) including dial number information including a telephone number of a telephone to be called and send the call signal to the subscriber accommodation server 11 in accordance with a user operation. it can. The subscriber's communication terminal may be a mobile phone in addition to a stationary telephone.

  The relay server 12 is configured to be able to communicate with each of the subscriber accommodation server 11, the subscriber accommodation server 13, and the sound source server 14. The relay server 12 relays the call control signal by performing a routing process for transferring a call signal, a response signal, and the like received from these devices. Note that the relay server 12 can be appropriately changed depending on the network configuration that constitutes the communication system 1, and is not necessarily configured by a server device. That is, the relay server 12 may be configured by, for example, a dedicated network (relay network) or a network device for relaying a call connection request.

  The subscriber accommodation server 13 has the following functions in addition to performing the same call control as the subscriber accommodation server 11. FIG. 2 is a block diagram showing a functional configuration of the subscriber accommodation server 13 shown in FIG. As shown in FIG. 2, the subscriber accommodation server 13 includes a setting unit 21, a communication control unit 22, an instruction unit 23, a first connection unit 24, a registration unit 25, a forced disconnection unit 26, a second connection unit 27, and a connection switching unit. 28.

  The setting unit 21 holds setting information for determining what kind of communication control processing is to be executed. The setting information stored in the setting unit 21 is congested due to a large amount of sudden call connection requests such as setting information for executing communication control processing that is executed in a normal time, a disaster, etc. There is setting information for executing a special communication control process that can deal with even a case. In this embodiment, the latter setting information, that is, setting information for executing a special call control process is held. The setting information stored in the setting unit 21 may be set in advance by a user who manages the communication system 1, for example, or may be set as needed. Alternatively, it may be automatically set according to the call control state of the subscriber accommodation server 13. An example of setting automatically is when the number of connections exceeds the upper limit of the number of connections allowed by the subscriber accommodation server 13, for example.

  The communication control unit 22 is connected to each of an instruction unit 23, a first connection unit 24, a registration unit 25, a forced disconnection unit 26, a second connection unit 27, and a connection switching unit 28, which will be described later, for communication terminals accommodated under the communication control unit 22 itself. An instruction is given to execute a communication control process. For example, the communication control unit 22 refers to the setting information held in the setting unit 21 and executes call control processing for a call connection request from the outside. In addition, the communication control unit 22 monitors the current connection state of the communication terminals accommodated in the communication control unit 22. In addition, when there is a call connection request to a communication terminal accommodated in the communication control unit 22, the communication control unit 22 instructs the connection state of the communication terminal serving as a connection source by an instruction unit 23 described later, and then connects to the connection destination. It is determined whether or not there is a free line necessary for connection to the communication terminal of the subscriber. The communication control unit 22 determines subsequent response processing for another communication terminal accommodated in the subscriber accommodation server 11 that has transmitted the call connection request, depending on whether or not there is an idle line.

  The instructing unit 23 instructs the subscriber accommodation server 11 that has transmitted the call connection request to place the subscriber's communication terminal in a connection waiting state. The subscriber accommodation server 11 instructed to enter the connection waiting state sets the communication path of the corresponding communication terminal to the sound source server 14. As a result, the subscriber's communication terminal in the connection waiting state enters a state in which automatic voice guidance is flowing (so-called talk state). Note that the communication terminal side may be notified not only of audio guidance but also of video, or not only of audio but merely of a provisional response signal (for example, provisional response signal 182 defined in RFC3261). You may comprise as follows.

  When it is determined that there is a free line, the first connection unit 24 connects to the communication terminal of the connection destination subscriber included in the call connection request.

  If it is determined that there is no free line, the registration unit 25 identifies the subscriber information of the connection source and the subscriber information of the connection destination from the transmitted call connection request, and puts these information in the idle waiting list. sign up. Thus, call connection requests waiting for connection are sequentially registered in the idle waiting list held by the subscriber accommodation server 13.

  The forced disconnection unit 26 forcibly disconnects a call connection that satisfies a predetermined condition. The predetermined condition here is, for example, a case where a certain time (for example, 5 minutes, 10 minutes, etc.) has elapsed since the connection between the communication terminals was established (when the call was established).

  When the forcible disconnection unit 26 forcibly disconnects the call, the second connection unit 27 assigns a new call connection to the free line generated by the disconnection, so that the call connection request registered in the idle waiting list The connection to the communication terminal is performed based on the above. The second connection unit 27 refers to the call connection registered next to the call connection to be assigned in the idle waiting list when the connection with the communication terminal as the connection destination fails, and the communication terminal Connect to the network sequentially.

  When the connection to the communication terminal of the subscriber as the connection destination is successfully connected by the first connection unit 24 or the second connection unit 27, the connection switching unit 28 sets the state of the communication terminal to the connection waiting state by the subscriber accommodation server 11. To the communication path for connecting to the connected subscriber. As a result, the communication terminal of the subscriber who made the call connection request and the communication terminal of the other subscriber as the connection destination are connected to enter a call state.

  Returning to FIG. 1, the sound source server 14 is a device in which audio data corresponding to the connection state of the communication terminal of the subscriber is stored. When the subscriber accommodation server 11 switches the communication path from the communication terminal that is the connection request destination to the sound source server 14, the subscriber communication terminal receives an automatic voice message based on the voice data stored in the sound source server 14. Played. A plurality of sound source servers 14 may be installed so as to be connectable from each of the subscriber accommodation servers 11a, 11b, and 11c.

  FIG. 3 is a flowchart showing a communication control process executed by the subscriber accommodation server 13 shown in FIG. Note that the communication control process shown in FIG. 3 is based on the premise that setting information for executing a special communication control process by the setting unit 21 is held as described above. This communication control process can be used for the affected areas of the subscriber accommodation servers installed in each area when a specific area is expected to be in a confused state due to factors such as a large earthquake. It is set and executed for the subscriber accommodation server. The state in which this special communication control process is set will be described using the term “affected state” for convenience.

  In the subscriber accommodation server 13 set in the affected state, the following processing is executed for each call connection request addressed to the communication terminal of the subscriber accommodated in the own server from the subscriber accommodation server 11 (START). The communication control unit 22 of the subscriber accommodation server 13 instructs the subscriber accommodation server 11 that has transmitted the call connection request to shift to a waiting state (step S1).

  On the subscriber accommodation server 11 side, in response to the instruction from the subscriber accommodation server 13 in step S1 to shift to the waiting state, the subscriber accommodation server 11 requests audio data (sound source) that conveys the connection waiting state to the sound source server 14. Then, the subscriber accommodation server 11 switches the communication path of the communication terminal of the subscriber who has made the call connection request from the communication terminal of the connection request destination to the sound source server 14, so that the communication terminal of the subscriber has a sound source server. The automatic voice message based on the voice data stored in 14 is reproduced and a so-called talkie connection state is established.

  The communication control unit 22 determines whether or not there is a free resource after instructing the transition to the waiting state in Step S1 (Step S2). If there is no free resource (No in step S2), the communication control unit 22 proceeds to the process of step S3, and if there is a free resource (Yes in step S2), the subscriber accommodation server 11 The communication terminal for which a call connection request has been made from is connected to the communication terminal of the subscriber accommodated in its own server (step S3).

  When the process of step S3 is executed and the connection with the communication terminal of the subscriber accommodated in the local server is successful, the communication control unit 22 automatically connects the communication terminal of the connection request source in the talk connection state. The subscriber accommodation server 11 is instructed to switch to the communication path of the communication terminal of the subscriber accommodated in the server.

  On the subscriber accommodation server 11 side, upon receiving a communication path switching instruction from the subscriber accommodation server 13, the communication path of the communication terminal of the subscriber that is in the talk connection state is switched to the communication terminal that is the connection request destination.

  Note that the communication terminal of the connection requesting subscriber who is in the talk connection state is not necessarily waiting for a response. Therefore, when the subscriber's communication terminal in the talk connection state is in a busy state or when there is no response for a predetermined time, the subscriber accommodation server 11 The corresponding audio data (sound source) is instructed to switch to the communication path of the connection request destination communication terminal. The subscriber accommodation server 13 switches the communication path of the subscriber's communication terminal accommodated in its own server to a connection that communicates that the connection request source communication terminal on the sound source server 14 cannot be connected to the automatic voice message. Play. Then, upon completion of the automatic voice message, the connection between the two is disconnected. This prevents the communication line from being occupied even though the communication service is not actually used by the connection request destination communication terminal only waiting for a response from the connection request source communication terminal. be able to.

  On the other hand, if it is determined in step S2 that there is no free resource, the registration unit 25 that has received an instruction from the communication control unit 22 assigns a number that increases in the registration order to the free waiting list, and waits for free space. The state is registered (step S4). In the idle waiting list, for example, subscriber information of a communication terminal serving as a connection source and subscriber information of a communication terminal serving as a connection destination are registered. When information is registered in the idle waiting list, the process proceeds to step S5.

  The communication control unit 22 monitors the call in the connected state, and determines whether there is anything to be forcibly disconnected (step S5). Forcibly disconnecting, for example, timer registration is performed on the subscriber accommodation server 13 side so that it can be executed when a certain period of time has elapsed since the connection (call) between the communication terminals was established. This should be done at the time of observation.

  If there is something to be forcibly disconnected in step S5, it is further determined whether there is a call connection request registered in the idle waiting list (step S6). If there is a call connection request registered in the idle waiting list (YES in step S6), the communication control unit 22 forcibly disconnects by the forced disconnection unit 26, and if not registered in the idle waiting list (step S6). In S6, the process ends (END). The forced disconnection unit 26 instructs the subscriber accommodation server 11 to switch the communication path for the call for executing the forced disconnection to the sound source server 14 and to reproduce the corresponding voice data on the communication terminal. The communication path for the corresponding call may be forcibly disconnected without instructing the sound source server 14 to switch.

  When the forced disconnection is completed, the communication control unit 22 assigns a free resource generated by the forced disconnection to a new caller. Therefore, the communication terminal of the connected subscriber to which the smallest number in this free waiting list is assigned. (Step S7).

  When the connection with the communication terminal of the connection destination subscriber is successful, the communication control unit 22 changes the voice path to the calling side subscriber from the state of the talk connection to the connection with the communication terminal of the connection destination subscriber. The subscriber accommodation server 11 is instructed to switch (step S8).

  As described above, a condition for executing forced disconnection is provided, and a new free line is generated on the subscriber accommodation server 13 side by performing the forced disconnection. Therefore, the generated free line is assigned the smallest number in the free waiting list. By assigning to the assigned caller, it is possible to sequentially connect to the subscribers waiting for the line. The operation after step S8 may return to the process of step S6. Further, the order of transition to the waiting state in step S1 and the determination of the presence or absence of the free resource in step S2 are reversed, and if there is no free resource, the transition to the waiting state is instructed. Subsequent processing may be performed.

  In the communication control process described above, the connection request from the communication terminal accommodated under the subscriber accommodation server 11 to the communication terminal accommodated under the subscriber accommodation server 13 has been described as an example. The same applies to communication terminals accommodated under the person accommodation server 13. In this case, since communication within the server itself has only to be established, the instruction to shift to the waiting state at step S1 in FIG. 5 and the connection switching instruction at step S8 to the subscriber accommodation server 11 may be omitted. Is possible. That is, in the case of a call between the communication terminals accommodated under the subscriber accommodation server 13, it can be executed from the resource determination in the free state which is the process of step S2, and the process of step S8 is performed by the subscriber. Connection switching processing can be executed in the accommodation server 13.

  FIG. 4 is a diagram showing a connection sequence when other communication control processing executed by the subscriber accommodation server 13 shown in FIG. 1 is realized by SIP (Session Initiation Protocol). The transaction shown in FIG. 4 starts when an INVITE request addressed to a communication terminal B of another subscriber is issued from the communication terminal A of the subscriber. As shown in FIG. 4, the INVITE request issued from the communication terminal A is transmitted to the subscriber accommodation server 13 via the subscriber accommodation server 11 and the relay server 12. When the relay server 12 receives the INVITE request, the relay server 12 returns a response (100 Trying) indicating that the communication server A is trying. This response notifies the communication terminal A that the INVITE request has been received and the relay server 12 is attempting to transmit the INVITE request to the communication terminal B on behalf of the communication terminal A.

  The subscriber accommodation server 13 that has received the INVITE request from the relay server 12 determines whether there is a free resource. If there is a resource, the subscriber accommodation server 13 sends an INVITE request to the communication terminal B accommodated in its own server. If there is no resource, the call is registered in a queue (corresponding to the idle waiting list described in FIG. 3). In this example, since there is no free resource, a message indicating that the INVITE request from the communication terminal A has been queued is transmitted from the subscriber accommodation server 13 to the subscriber accommodation server 11 (182 Queued). . The subscriber accommodation server 11 transmits an INVITE request for audio data to the sound source server 14 and reproduces a message indicating that the communication terminal A is waiting for connection.

Then, the subscriber accommodation server 13 executes a process of forcibly disconnecting when there is a call corresponding to a predetermined condition. Here, the predetermined condition is, for example, a case where a predetermined time has passed since the connection (call) between the communication terminals was established. Thereafter, because the queue is vacated by forced disconnection, the subscriber accommodation server 13 transmits an INVITE request from the communication terminal A registered in the queue to the communication terminal B. The communication terminal B that has received the INVITE request from the communication terminal A transmits a message indicating that the call is being made to the subscriber accommodation server 13 (180 Ringing). When the communication terminal B becomes ready for a call, the communication terminal B transmits to the subscriber accommodation server 11 via the subscriber accommodation server 13 and the relay server 12 that the INVITE request has been successful (200 OK). The subscriber accommodation server 11 transmits UPDATE to the communication terminal A and responds from the communication terminal A (200
When OK is returned, a message indicating completion is transmitted to the sound source server 14 (BYE), and a response (200 OK) is received. Then, an ACK message is transmitted to the communication terminal B, and a call process between the communication terminal A and the communication terminal B is started.

  The series of processes described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software executes various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a program recording medium in a general-purpose personal computer or the like.

  FIG. 5 is a block diagram illustrating an example of a hardware configuration of a computer that executes the above-described series of processes using a program.

  In the computer, a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, and a RAM (Random Access Memory) 53 are connected to each other by a bus 54.

  An input / output interface 55 is further connected to the bus 54. The input / output interface 55 includes an input unit 56 composed of a keyboard, mouse, microphone, etc., an output unit 57 composed of a display, a speaker, etc., a storage unit 58 composed of a hard disk and a non-volatile memory, and a communication unit 59 composed of a network interface. A drive 60 for driving a removable medium 61 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory is connected.

  In the computer configured as described above, the CPU 51 loads the program stored in the storage unit 58 to the RAM 53 via the input / output interface 55 and the bus 54 and executes the program, for example. Is performed.

  The program executed by the computer (CPU 51) is, for example, a magnetic disk (including a flexible disk), an optical disk (CD-ROM (Compact Disc-Read Only Memory), DVD (Digital Versatile Disc), etc.), a magneto-optical disk, or a semiconductor. It is recorded on a removable medium 61, which is a package medium composed of a memory or the like, or is provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting.

  The program can be installed in the computer by installing the removable medium 61 in the drive 60 and storing it in the storage unit 58 via the input / output interface 55. Further, the program can be installed in a computer by being received by the communication unit 59 via a wired or wireless transmission medium and stored in the storage unit 58. In addition, the program can be installed in the computer in advance by storing the program in the ROM 52 or the storage unit 58 in advance.

  The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program for processing.

  As described above, the subscriber accommodation server 13 sends a call connection request transmitted to the communication terminal of the subscriber accommodated under the subordinate to the subscriber accommodation which is another communication terminal of the own device or another communication control device. When receiving from the communication terminal accommodated under the server 11, the communication terminal that has transmitted the call connection request is notified of the connection waiting state, and the communication control unit 22 transmits to the communication terminal of the connected subscriber included in the call connection request. It is determined whether or not there is a free line necessary for connection. When it is determined that there is a free line, the first connection unit 24 connects to the communication terminal of the connection destination subscriber included in the call connection request. If it is determined that there is no free line, the registration unit 25 registers the connection source subscriber information and the connection destination subscriber information included in the previous connection request in the free waiting list, and monitors the call in the connected state. Applies to the prescribed conditions When the call is forcibly disconnected by the forcible disconnection unit 26 and the call is forcibly disconnected, the call to the communication terminal based on the call connection request registered in the idle waiting list in the idle line generated by the disconnection is sent. The connection is made by the second connection portion 27. For this reason, even if a sudden call connection request occurs and a congestion state occurs, an automatic voice announcement indicating that the line is waiting for use flows and the communication line becomes available. The connected users are connected sequentially. This makes it possible to repeatedly make a call and sequentially connect to the user who is the source of the congestion state, thereby eliminating the need for the user to make a call repeatedly. Also, by monitoring the connected call and forcibly disconnecting the call that meets the predetermined condition, the communication line can be used efficiently. In other words, even if a congestion state occurs due to a large number of call connection requests, it is possible to eliminate the congestion state by sequentially connecting so that it is not possible to contact at all, and to stabilize the call service early. it can. In particular, in the case of a large-scale disaster, the congestion state in the subscriber accommodation server 13 can be restored relatively early, and the call time for confirming the safety is set for the subscriber, although at regular intervals. Can be secured every time.

  Further, as a predetermined condition for the forced disconnection unit 26 to forcibly disconnect the call connection, the subscriber accommodation server 13 determines that the connection destination subscriber's connection is established when a predetermined time has elapsed since the connection between the communication terminals was established. When the connection state of the communication terminal is busy for a certain period of time, it is at least one of cases where there is no response from the communication terminal of the connection destination subscriber. As a result, even for calls that are already connected, connections that are not actually functioning as a call service, or those that have been connected for a certain time or longer are forcibly disconnected, so that the entire call connection request On the other hand, the communication line can be used efficiently.

  Further, the communication control method related to call connection executed by the subscriber accommodation server 13 and the program installed in the subscriber accommodation server have the same effects as the above-described effects produced by the subscriber accommodation server 13. is there.

  The embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, although it is mentioned that the disaster state is set as a condition to be set as the subscriber accommodation server 13, an arbitrary server requests more than the allowable number of simultaneous connections due to the occurrence of any congestion without performing this setting. In such a case, the communication control method described in the above-described embodiment can be automatically applied.

  DESCRIPTION OF SYMBOLS 1 ... Communication system 11, 11a, 11b, 11c ... Subscriber accommodation server (an example of another communication control apparatus), 13 ... Subscriber accommodation server (an example of communication control apparatus), 22 ... Communication control part (of determination means) (Example), 23 ... Instruction section (means for regenerating) 24 ... First connection section (example of first connection means), 25 ... Registration section (example of registration means), 26 ... Forced disconnection section (example of forced disconnection means) , 27 ... second connection part (an example of second connection means),

Claims (4)

When a call connection request transmitted to a communication terminal of a subscriber accommodated in a subordinate is received from a communication terminal accommodated in another communication terminal of the own apparatus or another communication control apparatus, the communication terminal of the subscriber In a communication control device that executes call connection to
Means for notifying the communication terminal that has transmitted the call connection request of a connection waiting state;
Determining means for determining whether or not there is a free line necessary to connect to the communication terminal of the connection destination subscriber included in the call connection request;
First connection means for connecting to the communication terminal of the connection destination subscriber included in the call connection request when it is determined by the determination means that the idle line is present;
Registration means for registering connection source subscriber information and connection destination subscriber information included in the call connection request in an idle waiting list when the determination means determines that there is no free line;
A forced disconnection means for monitoring a call in a connected state and forcibly disconnecting a call corresponding to a predetermined condition;
Second connection means for connecting to the communication terminal based on the call connection request registered in the idle waiting list in the idle line generated by the disconnection when the call is forcibly disconnected by the forcible disconnecting means. When,
A communication control device comprising: The communication control device according to claim 1,
The predetermined condition for the forced disconnection means to disconnect the call connection is that when a predetermined time has elapsed since the connection between the communication terminals was established, the connection state of the communication terminal of the connection destination subscriber is busy for a certain time. If there is, the communication control device is at least one of the cases where there is no response from the communication terminal of the connection destination subscriber. When a call connection request transmitted to a communication terminal of a subscriber accommodated in a subordinate is received from a communication terminal accommodated in another communication terminal of the own apparatus or another communication control apparatus, the communication terminal of the subscriber In a communication control method for executing a call connection to
Notifying the communication terminal that has transmitted the call connection request of a connection waiting state;
A determination step of determining whether or not there is a free line necessary for connecting to the communication terminal of the connection destination subscriber included in the call connection request;
A first connection step of performing connection to the communication terminal of the connection destination subscriber included in the call connection request when it is determined by the determination step that the idle line is present;
A registration step of registering connection source subscriber information and connection destination subscriber information included in the call connection request in a waiting list when it is determined by the determination step that there is no free line;
A step of notifying the communication terminal that has transmitted the call connection request of the connection waiting state when it is determined by the determination step that the free line is not present;
A forced disconnection step of monitoring a connected call and forcibly disconnecting a call corresponding to a predetermined condition;
A second connection step of connecting to a communication terminal based on the call connection request registered in the idle waiting list in an idle line generated by the disconnection when the call is forcibly disconnected by the forcible disconnection step; When,
The communication control method characterized by including. When a call connection request transmitted to a communication terminal of a subscriber accommodated in the subordinate is received from another communication control device, a computer that executes a call connection to the communication terminal of the subscriber,
Means for notifying the communication terminal that has transmitted the call connection request of a connection waiting state;
Determining means for determining whether or not there is a free line necessary to connect to the communication terminal of the connection destination subscriber included in the call connection request;
First connection means for connecting to the communication terminal of the connection destination subscriber included in the call connection request when it is determined by the determination means that the idle line is present;
Registration means for registering connection source subscriber information and connection destination subscriber information included in the call connection request in an idle waiting list when the determination means determines that there is no free line;
A forced disconnection means for monitoring a call in a connected state and forcibly disconnecting a call corresponding to a predetermined condition;
Second connection means for connecting to the communication terminal based on the call connection request registered in the idle waiting list in the idle line generated by the disconnection when the call is forcibly disconnected by the forcible disconnecting means. ,
Program to function as.

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