JPS587103B2 - Store-and-forward congestion control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to reduce the influence of congestion generated in a storage/conversion device on the storage/conversion network and facsimile communication service in, for example, a facsimile communication switching network that employs a store-and-forward system in which a lower-order network is shared with a telephone network. The present invention relates to a method of controlling congestion that is solved by minimizing the amount of noise.

In a conventional communication network using a circuit switching system, when a call is made, a train from the calling terminal to the receiving terminal is secured before communication information is transmitted.

Therefore, when congestion occurred, it was possible to determine the congestion condition at the stage of securing the relevant train.

However, in a method such as the store-and-forward method, in which facsimile J signals are temporarily stored in the communication network and transferred from the transmitting (calling) terminal to the receiving (receiving) terminal, it is not possible to check whether the receiving party is ready for reception. ＼Facsimile J signals are accepted and accumulated in the network without limit, and as a result, when congestion occurs on the receiving side, the communication network side informs the caller that the information that has been accepted and accumulated in the communication network is considered a lost call. Will you notify me?
Alternatively, it becomes necessary to continue storing data in a storage/conversion device capable of storing data until a call can be received, which affects the entire storage/transition network.

According to this invention, when a storage/conversion device enters a congested state, this is detected and the exchange in which the storage/conversion device is accommodated is notified to indicate that the storage/conversion device is in a congested state.

When an outgoing call from a subscriber accommodated in the exchange or an incoming call to a subscriber accommodated in the exchange occurs via the store-and-forward device in the congestion state, the congestion display will be displayed. In some cases, such calls will be restricted.

Therefore, no needless facsimile transmission is performed, and the communication network can be used more effectively.

When the congestion of a storage/conversion device in a state of contrast is restored, this is notified to the switch in which the storage/conversion device is accommodated.

Therefore, the call restriction is lifted.

Next, an embodiment of the store-and-forward congestion control method according to the present invention will be described with reference to the drawings.

Subscriber A's push-button telephone 11 and facsimile is accommodated in the subscriber line exchange 13.

Subscriber B's push-button telephone 14 and facsimile terminal 1
5 is accommodated in the subscriber line exchange 16.

The subscriber line exchanges 13 and 16 are each connected to a telephone exchange 17.
For example, the telephone exchange 17 houses storage and forwarding devices 21 and 22, and the telephone exchange 18 houses a storage and forwarding device 23.
．． 24 are accommodated.

Storage conversion device 21. 22 are both storage conversion devices 25.2
storage conversion device 23 . 24 are also connected to any of the storage and conversion devices 25 and 26.

The storage and conversion devices 21, 22, 23, and 24 each convert, for example, a facsimile signal from a telephone exchange into a digital signal, compress and encode it, and transmit it to a subsequent storage and conversion device, and vice versa. It has conversion and storage functions such as decoding and decompressing the code from the terminal, converting it into an analog signal, and supplying it to the subsequent telephone exchange.

The storage/conversion devices 25 and 26 have a relay function of receiving and storing code signals from the preceding storage/conversion device and then transmitting them to the subsequent storage/conversion device.

Facsimile signals can be exchanged between telephone exchanges 17 and 18 through various routes through these storage and conversion devices.

Further control takes place via a common line 29 connected between them through common line signaling devices 27, 28 belonging to each exchange 17, 18.

Further, the common line signaling devices 31, 32 of the telephone exchange 17 are connected to the common line signaling devices 33.32 of the storage/converting devices 21, 22. 34, respectively, and the common line signaling devices 35, 36 of the telephone exchange 18 are connected to the common line signaling devices 37, . 38 respectively.

Each of the storage and conversion devices 21 to 26 has a congestion detection device 41 to 46 that detects the width/light state of the device by, for example, checking the sufficiency state of its memory, and displays this when the congestion is detected. Convergence state display devices 47 to 52 and adjacent convergence state display devices 53 to 58 for displaying the convergence states of adjacent storage conversion devices are provided, respectively.

Furthermore, the telephone exchange 17, 18 is provided with an adjacent congestion status display device 61, 62 for displaying the congestion status of the adjacent storage/conversion device.

For example, if congestion occurs in the storage/conversion device 21, its contrast detection device 41 detects the congestion, displays the congestion on the congestion status display device 47 of the storage/conversion device 21, and at the same time alerts the adjacent telephone. Common line signaling device 3 for exchange 17
3 to transmit the congestion status signal to the common line signaling device 31 of the telephone exchange 17.

The telephone exchange 17 receives this and displays on the adjacent congestion status display device 61 that the storage conversion device 21 is busy.

In this state, a method for regulating outgoing calls when the storage/converting device that is busy becomes the calling side will be described first.

When subscriber A dials the special number and the called subscriber number using the pushbutton telephone 11, the subscriber line converter 13 dials the calling subscriber number, the service type special number, and the called subscriber number, for example, the number of subscriber B. It is transmitted to the telephone exchange 17.

The telephone exchange 17 identifies the storage/conversion device 21 in a light congestion state based on the display state of the adjacent congestion state display device 61, and restricts outgoing calls by, for example, transmitting a talkie.

Next, a description will be given of outgoing call regulation when the storage/conversion device 21 that is busy becomes the receiving side.

When subscriber B dials a special number and the called party's number, for example the number of subscriber A, from the push-button telephone 14 to make a call, the telephone exchange 18 identifies the called telephone exchange 17. The communication line devices 27 and 28 are used to refer to the adjacent comparison status display device 61 of the terminating telephone exchange 17.

By this reference, the receiving side storage and conversion device 2 for subscriber A
1 is busy and this is communicated to the originating telephone exchange 18 via the common signal line device 27,28.

As in the previous case, outgoing calls are restricted (talkies are sent out) at this point.

As described above, according to the present invention, when a certain storage and conversion device becomes congested, the storage and conversion device is prevented from being captured.
Calls will be restricted at the time of making a new call.

Therefore, there is no possibility that a call is lost when the facsimile signal is sent halfway through the facsimile communication network, and there is no risk of unnecessary transmission.

Calls are restricted as described above, and when the congestion eventually recovers, the contrast detection device 41 detects it, erases the display on the contrast status display device 47, and at the same time A congestion release signal is sent to the exchange 17, and the congestion display of the storage conversion device 21 displayed on the adjacent comparison state display device 61 is erased.

Therefore, the call restriction is lifted.

As explained above, according to the present invention, traffic control is performed that restricts the origination of new calls that attempt to communicate facsimile signals via a store-and-transfer device during congestion. It is possible to prevent unreceivable facsimile J signals from being accumulated in the communication network.

Although the above-described embodiments are directed to the facsimile J store-and-forward network, the present invention can be applied not only to facsimiles but also to telephones that use the store-and-forward method.

[Brief explanation of drawings]

The figure is a block diagram showing an embodiment of the store-and-forward congestion control method according to the present invention. 11.14... Push-button telephone, 12, 15... Facsimile terminal, 13, 16... Subscriber line exchange, 1
7.18...Telephone exchange A19...Facsimile I communication network, 21-26...Storage and conversion device, 2γ, 28, 3
1-38... Common line signal device, 41-46... Traffic light detection device, 47-52... Traffic condition display device, 53-
58, 61, 62... Adjacent congestion state display device, 29.
...Common signal path.

Claims (1)

[Claims] 1. The lower network is shared with the telephone network, and storage and conversion devices unique to each subscriber are connected and accommodated in the corresponding telephone exchanges, and storage and conversion is carried out between the corresponding telephone exchanges through these unique storage and conversion devices. In a store-and-forward communication network that employs a store-and-forward method in which information is sequentially stored and transferred for each predetermined information unit by a device and information is transmitted from a transmitting terminal to a receiving terminal, the unique store-and-convert method described above A telephone installed in a device that detects the occurrence of congestion when congestion occurs in the storage conversion device, and transmits a signal indicating the congestion state to a telephone in which the storage conversion device in which the congestion occurs is housed. Congestion notification means for notifying the exchange; and a congestion notification means provided in the unique storage and conversion device, which detects the recirculation of the width when the congestion of the storage and conversion device is restored, and sends a signal indicating that the congestion has been reduced. Convergence recovery notification means for notifying the telephone exchange in which the storage and conversion device in which the congestion has been restored is housed; Among outgoing calls and incoming calls to the same terminal equipment group, for new calls that go through a unique storage and conversion device accommodated in the telephone exchange, the congestion or 1. A storage-and-forward width control method, comprising a control means for notifying a state of contrast recovery and for restricting or canceling transmission restrictions for a corresponding storage and conversion device.