JPH0691677B2 - Call control system - Google Patents

Description

The present invention relates to a call processing control system for an electronic exchange, and more specifically, in addition to a state transition group corresponding to an actual terminal device (hardware terminal), for example, another The present invention relates to a call control method for easily realizing service processing by installing a state transition group corresponding to a special service such as a person's call.

[Background of the Invention] In an electronic exchange of storage program control, there are an integrated type and a distributed type in a call control method by a state transition description.

The integrated type is typically, for example, the one shown in "D10 type automatic exchange part 9 (switching station program-part 1)", page 10-13, issued by Dentsu Public Corporation. All the terminals involved in the states are described, and transitions are made between the states. This integrated system has a problem that the program description increases as the number of terminals involved increases, and call control becomes complicated.

The distributed system was devised to prevent the above-mentioned drawbacks, and for example, the Institute of Electronics and Communication Engineers, Journal Vol. J65-B, No. 6, 1982.
Has been reported to. In this method, the state transition group is divided for outgoing / incoming correspondence or terminal correspondence, and the state of the call is expressed by a combination of them. For special services such as other party calls, it is embedded in an appropriate state group. Has become. However, this decentralized method has some problems in control because there are some services that cannot be expressed by a combination of the states of each terminal or some services are extremely complicated, especially for services involving others.

[Object of the Invention] An object of the present invention is to provide a call control system that is easy to describe the state and has excellent maintainability even when a special service function is involved.

Another object of the present invention is to provide a call control system that facilitates terminal control during service execution.

[Summary of the Invention] In order to achieve the above object, the call control system of the present invention comprises:
By installing a service-compatible terminal state group for performing service-specific processing and exchanging messages between the service-compatible terminal state group and the hardware terminal state transition group corresponding to the actual terminal device, The feature is that the increase in the program description amount and the complexity of call control are prevented.

That is, in the present invention, in a call processing service, for a special service that requires a state sequence for service control, such as a three-party call, this is regarded as a virtual terminal, Similar to an actual hardware terminal, a state transition group corresponding to the service is provided for these services, and a control message is transmitted and received between these state transition groups to perform call control. Further, by storing the call status number, the other terminal accommodating position information, and the like in the service corresponding terminal memory allocated on the main storage device, all service specific processing is performed by the service corresponding state transition group.

[Embodiment of the Invention] 1. Description of Configuration FIG. 1 shows an example of the configuration of an electronic exchange system to which the present invention is applied. The exchange system 1 includes a speech path switch 5 for exchanging information, a central processing unit 6 for controlling call processing, and a main storage unit 7. The area of the main memory 7 is composed of a program section and a data section. The program section stores a state transition control program, a call processing task program, and a signal transmission / reception program. The data section has a terminal memory area and a keyhole table. It consists of an area.

Call control for this kind of electronic exchange is generally performed by a state transition control method. The state transition control should be executed by, for example, storing a “call state” such as “calling” or “calling” in the main storage device 7 as information unique to the terminal and combining the state and the detected change. Determines call processing (called a task). The above control is performed by the state transition control program.

In a state transition control type electronic exchange, an information storage area corresponding to a terminal (hereinafter referred to as a terminal memory) is prepared in the terminal memory area, and the state of the terminal is stored as a state number.

FIG. 2 shows the structure of the terminal memory. The terminal memory comprises a terminal memory primary table 8 indexed by terminal port number, and a terminal memory secondary table 9 accessed by the pointer address information stored in this primary table.

In the terminal memory secondary table 9, in addition to the state number indicating the current call state of that terminal, resource related information such as position information indicating the accommodation position of the connection partner terminal and path information indicating the currently connected path. And billing information and information indicating various condition memories are stored.

The partner terminal accommodation position information is referred to when the status change information is transmitted to the partner terminal. For example, when two terminals (subscribers A and B) 2 connected to the same exchange 10 are in a call, the switch operation is as shown in FIG. 3, and at this time, the state of the terminal memory is as shown in FIG. Like

That is, in the terminal memory primary table 8, the terminal A
The address pointing to the terminal memory secondary table for terminal A is stored in the storage location searched for by port number 12 of
The terminal memory secondary table address for the terminal B is stored in the storage position searched by the port number 13 of the above. Also,
The terminal accommodation position information of the other party in the terminal memory for the terminal A is set to the port number of the terminal B, and the terminal accommodation position information of the other party in the terminal memory for the terminal B is set to the terminal A port number. .

2. Description of Operation Here, the call processing control operation according to the present invention will be described by taking a “holding service” as an example of the special service.

Holding service is a terminal (terminal / trunk)
When the person who handles terminal A hooks terminal A while A and B are in a call, dials the third terminal (terminal / trunk) C, and when terminal CC answers, A-C calls This is a service in which the terminal B is put in the middle and is held.

FIG. 6 is a diagram showing a state of the switch at the time of the holding service, in which the terminal A connected to the SUBT11 and the terminal (relay line) C connected to the trunk 4 are connected,
The terminal (relay line) B connected to the trunk 4 is connected to the hold tone generating circuit 17. After that, every time the person who handles the terminal A hooks the terminal A, a call between A and B,
The call switches to A-C. Further, when the terminal A is disconnected, the communication state between B and C is established.

The call processing operation according to the present invention in the above holding service will be described below focusing on the configuration of the terminal memory.

The state of the terminal memory during a call between the terminal A and the terminal B is as shown in FIG. 4 described above. The person who handles terminal A is terminal A
When the hooking operation is performed, the speech path switch 5 shown in FIG. 1 detects the hooking signal and notifies the central processing unit 6 of the hooking signal. As a result, the state transition control program in the main storage device 7 is activated.

The state transition control program accesses the terminal memory primary table 8 during the call based on the port number 12 of the terminal A that generated the hooking signal, and based on the obtained memory address, the terminal memory 9 for the terminal A ( Read A). In this case, since the current state number indicates that a call is in progress, the holding service task in the call processing task program on the main storage device is activated.

The operation contents of the holding service task will be described below.

As shown in FIG. 5, the holding service task captures one of the holding service terminal memories 16 in the empty state according to the pointer address registered in the holding service terminal memory idle chain. These holding service terminal memories 16 are control memories for virtual terminals, which are prepared for each service, rather than for existing ordinary terminals.

In addition, in the idle chain, the head one of the plurality of virtual terminal memories 16 in the empty state is the head pointer 14
, The last one is specified by the tail pointer 15.These virtual terminal memories are sequentially linked by the next terminal memory address stored in each virtual terminal memory, and the next terminal memory of the chained final terminal memory is sequentially linked. The terminal memory address is set to 0 to indicate that it is the final address. In addition, in each virtual terminal memory 16,
A unique virtual terminal port number is set.

The above-mentioned capture of the virtual terminal memory secures the final free state virtual terminal memory indicated by the tail pointer 15 (removes it from the chain), and accordingly, the value of the tail pointer 15 and
This means updating the value of the next terminal memory address of the newly finalized virtual terminal memory.

The holding service task stores the captured address of the virtual terminal memory 16 in the terminal memory primary table 8 corresponding to the virtual terminal port number 21 set in the virtual terminal memory 16 as shown in FIG. Set to the memory location. Further, the relay line (terminal B) of the transistor 4 which has been connected to the terminal 2 (terminal A) until then is disconnected, and the trunk 4 (terminal B) is connected to the hold tone HT17.

After that, the state of the holding call according to the present invention is expressed as follows according to the state transition group corresponding to the hardware terminal memory 9 and the state transition group corresponding to the captured service terminal memory 16. It

Now, assuming that the operator of the terminal 2 (terminal A) in FIG. 6 dials the number corresponding to the trunk line (terminal C) of the trunk 4, the dial information is transmitted via the state transition group corresponding to the terminal 2. Then, it is transmitted as a message to the state transition group of the holding virtual terminal, and the call processing task in the holding service terminal is activated.

The call processing task in the holding service terminal is, as shown in FIG. 7, a terminal memory secondary table 9 corresponding to the terminal 2 (terminal A), the trunk line (terminal B), and the trunk line (terminal C). To the other party's terminal position number Aria,
Set the port number 21 of the virtual terminal. Also. The port number of the terminal A, the port number of the terminal B, and the port number of the terminal C are stored in the virtual terminal memory 16. At the same time, the terminal 2 (terminal A) is connected to the trunk 4 trunk line (terminal C).
And the state shown in FIG.

During the holding service, the events that occurred on the terminal are
It is not processed by each terminal and is transmitted as a change signal to the virtual terminal. Control (setting / disconnection) of the communication path is performed on the virtual terminal side.

When the terminal A rehooks in the state shown in FIG. 7, a hooking signal is transmitted to the virtual terminal, and the virtual terminal sets the states AB (in communication) and C (hold).

FIG. 8 shows a conventional terminal memory configuration for achieving the functions described above. Each terminal memory stores a plurality of partner terminal accommodating position information (terminal port numbers), and when a change event occurs in a terminal, call path connection control is performed in each terminal and shows the change information. The control signal is transmitted to all the other terminals based on the partner terminal accommodation position information. Also, each terminal receiving the control signal,
The processing according to the type of the received signal is individually performed, and the information in the terminal memory is updated. Therefore, for example, when a holding service occurs, a special process for the holding service is included in each terminal process, and the process at each terminal becomes complicated as the number of services increases.

In this example, the services of the three parties (A, B, C) were taken up, but in the case of a service involving a larger number of terminals such as the conference telephone service, the complexity of processing and the increase in the amount of programs / data accompanying it Therefore, it is extremely difficult to deal with the problem with the conventional method.

On the other hand, the present invention can easily realize services such as call waiting, Mauritius call, add-on, camp-on-busy, SVI, wake-up, and call forwarding, in addition to the holding service described above.

[Advantages of the Invention] The method of the present invention in which a virtual terminal group is provided for a special service can (1) reduce the number of states by 6.5 on average as compared with the conventional method.

(2) The program size can be reduced by 20% on average.

(3) The load on the central controller by communication is about 1.2 times on average, and there is no problem in performance.

It is also effective in improving maintainability by simplifying the state description.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a system configuration of an electronic exchange to which the present system is applied, FIG. 2 is a diagram showing a configuration of a terminal memory, FIG. 3 is a switching operation explanatory diagram of a two-party subscriber call, and FIG. FIG. 5 is a terminal memory state explanatory diagram corresponding to FIG.
FIG. 6 is a diagram showing an idle chain of a virtual terminal memory for a holding service, FIG. 6 is an explanatory diagram of switching operation during a holding service, FIG. 7 is a state explanatory diagram of the terminal memory corresponding to FIG. 6, and FIG. It is a block diagram of the terminal memory by a conventional system. Explanation of symbols 1 ... Electronic exchange, 2 ... Subscriber, 3 ... Relay stand, 4 ...
... Trunk, 5 ... call path switch, 6 ... central processing unit, 7 ... main memory, 8 ... terminal memory primary table, 9 ... terminal table secondary table, 10 ... call path switch, 11 ...... SUBT, 12 …… A terminal port number, 13 ……
B terminal port number, 14 ... holding terminal memory idle chain head pointer, 15 ... same tail pointer, 16 ... holding terminal memory, 17 ... hold tone generation circuit, 18 ... ringback tone generation circuit, 19 ...... Busy tone generation circuit, 20 …… C terminal port number, 21 …… Virtual terminal port number

Claims (2)

[Claims] 1. In a call processing control system in which a state transition is performed according to a combination of a call state in an electronic exchange and a change event of a terminal by a storage program, for a state transition control prepared for each block for each terminal. Has a first memory block group and a second memory block group for state transition control prepared for each virtual terminal, and when a special service request is made during a call, the corresponding service task A plurality of blocks of a first memory block group that captures an empty virtual terminal-compatible memory block from the second memory block group and that corresponds to the plurality of terminals in communication. The state transition is controlled by the memory block corresponding to the virtual terminal for the event that occurred in the terminal while executing the special service. Call control method in which the butterflies. 2. When a connection service of three or more parties is executed as the special service, a task for the connection service is provided in each block of the first memory group corresponding to a plurality of terminals related to the connection service. The identification information of the block corresponding to the virtual terminal captured by the device is stored, and the identification information of the block corresponding to each of the terminals is stored in the block corresponding to the virtual terminal. When an event occurs, the change event is notified to the virtual terminal corresponding block linked by the identification information stored in the block corresponding to the terminal, and the call path is controlled by the state control in the virtual terminal corresponding block. The call control system according to claim 1, wherein the call control is performed.