JPS63187839A - Relay transmission system in facsimile store and forward exchange network - Google Patents

Abstract

PURPOSE:To attain the relay transmission even at a fault of a private channel while improving the utilizing efficiency by connecting store and forward exchanges at the sender and receiver sides by plural channels, and selecting one of the said channels at the sender side, and relaying and sending a data to the reception side. CONSTITUTION:A store and forward exchange 1A is provided with a communication control section 10A, a central control section 11A and a storage section 12A, the communication control section 10A is mounted with plural channels 10-1A-10-nA and they are connected to a line network 3. This is applied similarly to a store and forward exchange 1B. In applying relay and transmission from the exchange 1A to the exchange 1B and when a subscriber calls from the communication control section 10A, an idle channel is selected from said plural channels 10-1A-10-nA for the call. A channel selected from plural channels 10-1B-10-nB is assigned to a communication control section 10B at the receiver side.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a data transmission system in a facsimile store-and-forward network, and particularly relates to facsimile storage when data is transmitted via communication between store-and-forward devices. Relates to relay transmission systems in switched networks.

(Prior Art) Data transmission between facsimile terminals located over a long distance, such as between Tokyo and Osaka, is generally performed via a relay between storage and forwarding devices in a facsimile store and forwarding network.

In the relay transmission system in this type of conventional facsimile store-and-forward network, data arriving from the sender's facsimile terminal to the sender's store-and-forward device is sent to the receiver's store-and-forward unit via channels and lines specially provided for relay transmission. After transmitting the information to the storage and forwarding device, the information is distributed from the storage and forwarding device to the receiving facsimile terminal.

For this reason, for example, when requests for relay transmission occur frequently, a considerable amount of waiting time is required, resulting in a decline in line usage efficiency.

Further, if some kind of failure occurs in the dedicated channel or line mentioned above, relay transmission may become impossible due to lack of alternative means.

゛(Problem that Ikei is trying to solve) As described above, the relay transmission method in the conventional facsimile store-and-forward network uses a dedicated channel and line for relay transmission, so the line usage efficiency is poor. There is a problem in that if a failure occurs in the channel or line, relay transmission becomes impossible.

The present invention has been made in view of the above-mentioned circumstances, and has high line utilization efficiency, and also enables relay transmission even when a dedicated channel or line fails, thereby increasing the reliability of the relay transmission. It is an object of the present invention to provide a relay transmission system in a facsimile store-and-forward network that can be improved.

[Structure of the Invention] (Means for Solving the Problems) The relay transmission method in the facsimile store and forward network of the present invention is such that the transmitter store and forward device and the receiver store and forward device are connected via a plurality of channels. The transmitting storage and forwarding device is characterized in that it selects one channel from the plurality of channels and relays the data to the receiving storage and forwarding device.

(Function) In the relay transmission system in the facsimile store-and-forward network of the present invention, all channels between the transmitter-side store-and-forward device and the receiver-side store-and-forward device are dynamically controlled, and data can be relayed and transmitted without specifying channels and lines. By doing so, the above objective has been achieved.

(Example) Examples of the present invention will be described in detail below based on the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of a facsimile storage and forwarding system according to the present invention, and shows a storage and forwarding device 1A.
, storage and forwarding device 1B, and facsimile terminals 28 to 2N are each connected through circuit N12J3.

Of these, the storage and forwarding device 1A is configured to include a communication control section 1A, a central control section 11A, and a storage section 12A. 12B.

Further, the communication control unit 10A controls a plurality of channels 10-1A.
, 10-2A, . . . , 10-nA, and these channels 1O-IA.

1O-2A, . . . , 1O-nA are each connected to the line network 3.

The configuration of this communication control unit 10A is a plurality of channels 10-IB each connected to the line network 3.

This is the same as the communication control unit 10B that implements 1O-2B, . . . , 1O-nB.

Now, in FIG. 1, consider the operation when data received from the facsimile terminal 2A to the storage/forwarding device 1A is distributed to the facsimile terminal 2N via relay transmission with the storage/forwarding device 1B.

In this case, the data transmitted from the sending facsimile terminal 2A to the sending storage and forwarding device 1A via the line network 3 is transmitted to the communication control unit 10A under the control of the central control unit 11A.
Multiple channels 1O-1A, 10-2A, ...
----, 10-nA, and is stored in the first section 12A via a channel that is an idle line.

Next, the central control unit 11A transmits the data stored in the storage unit 12A to the storage and forwarding device 1B on the receiving side via the line network 3. An example of the operation at this time will be explained in detail with reference to the flowchart in FIG. 2). Yes.

First, the central control unit 11A determines whether or not a request for relay transmission of the data has been made before starting the transmission of the aforementioned data to the storage and forwarding device @1B on the receiving side (step 100).

This determination is made, for example, by a receiving facsimile terminal 2 that receives a call at the sending storage and forwarding device 1A using a prescribed protocol prior to the transmission of the data from the sending facsimile terminal 2A.
This can be done based on the dialed number of N.

When it is determined in step 100 that a request for relay transmission of the data has been made, the central control section 11A next selects which channel (10-1B) of the communication control section 10B on the receiving side.

, 1O-n8), which of the communication control units 10A on the transmitting side 1! Channel number (10-IA, ~, 10-nA) on the receiving side to instruct whether to make a call from
) and transmitting channel number (TC
For example, set the H-No.) in order starting from number 1 (
Steps 101°102).

Subsequently, the central control unit 11A selects the channel (1) corresponding to the transmitting side channel number set in step 102.
0-IA, ~, 10nA) is in use or not (step 103), and only when it is determined that it is not in use, the channel number corresponding to the receiving side channel number set in step 101 is determined. Channel (10-1B, =
, 1o-nB) (step 104).

Further, the central control unit 11A determines whether or not the line (existing in the line network 3) between the transmitting side channel and the receiving side channel has been connected in the above-described call origination (step 105). ), and when it is determined that the connection has been established, the data stored in the storage section 12A is sent to the line through the transmission channel according to a prescribed facsimile procedure (step 106).

On the other hand, in the storage and forwarding device 1B on the receiving side, the data sent to the line through the transmission channel is received through the reception channel in the communication control unit IOB under the control of the central control unit 11B, and is temporarily stored. The information is stored in the section 12B.

By the way, if it is determined in step 103 that the channel corresponding to the channel number on the transmitting side set in step 102 is in use, then the central control unit 11A controls the channel number on the transmitting side. Number (RCH-No.

) and the predetermined maximum channel number (TMAX
) to determine whether the channel number settings on the transmitting side have been completed for all channel numbers (step 1o7).

In the judgment at step 107, TCH-No, <
While it is determined that the settings for all channel numbers on the transmitting side have not completed a cycle due to the condition TMAX, the central control unit 11A adds 1 to the channel numbers on the transmitting side that have been set up to that point. By this, the next channel number is newly set (step 108). Further, if it is determined that the settings for all channel numbers on the transmitting side have been completed based on the condition of TCH-No, ≧TMAX, the central control unit 11A performs step 102.
Returning to the process described above, setting of the transmitting side channel number starts again from number 1.

In this way, the central control unit 11A repeatedly executes the processes of steps 107, 108 and 102 until it finds a channel number on the transmitting side that is not in use in step 103, and at the same time it finds the channel number on the transmitting side that is not in use. After the above processing, a call is made to the storage and forwarding device 1B on the receiving side.

Further, in the determination in step 105 regarding whether or not a connection has been made for this call, if it is determined that no connection has been made, the central control unit 11A selects the corresponding channel number (RCH) of the receiving side that made the current call. -No,)
The maximum channel number on the receiving side (R
MAX), and it is determined whether the setting of the channel number of the receiving side as the calling target has been completed for all channel numbers (step 109).

In the judgment at step 109, RCH-No, <
While it is determined that the settings for all channel numbers on the receiving side have not completed a cycle due to the RMAX condition, the central control unit 11A adds 1 to the channel numbers on the receiving side that have been set up to that point. As a result, the next channel number is newly set (step 107).

Also, if it is determined that the settings for all channel numbers on the receiving side have been completed under the condition that PCI-(-No, ≧RMAX), the central control unit 11A returns to the process of step 101 and starts from number 1 again. Start setting the receiving channel number.

In other words, the center plate section 11A repeatedly executes the processes of steps 109, 110, and 101 at the time when the connection with the storage and forwarding device 1B on the receiving side is confirmed in step 105.
When the channel corresponding to the channel number of the receiving side that made the call is in an unused state, the connection to the source channel for the call from the channel of the sending side is confirmed, and at the same time, through the process of step 106, the receiving side The transmission of the data to the storage/forwarding device 1B is started.

In this way, in the present invention, when performing relay transmission from the storage and forwarding device [IA to the storage and forwarding device 1B, the communication control unit 10A
When making a call, instead of using a specific channel to make a call, you can use multiple channels 1O-1A,...
. . . A call is made by selecting an empty channel from 10-nA.

Also, at this time, the channel of the communication control unit 10B on the receiving side is selected from a plurality of channels 10-IB, . . . , 1O-nB without using a specific channel. That's what I do.

The data accumulated and stored in the storage unit 12B of the transshipment device 1B under such control is subsequently stored in a plurality of channels 1O in the communication control unit 10B under the control of the central control unit 11B.
-1B, 1O-2B,...

It is delivered to the receiving facsimile terminal 2N via a channel that is an idle line among the 10-nB channels.

〔Effect of the invention〕

As explained above, according to the relay transmission system in the facsimile store-and-forward network of the present invention, all channels of the transmitting-side store-and-forward device and the receiving-side store-and-forward device are dynamically controlled, and the transmitting-side store-and-forward device identifies idle lines and Data is relayed between the transmitting store and forwarding device and the receiving store and forwarding device through a line established between the channel selected by the receiving store and forwarding device and the channel selected from the receiving store and forwarding device. It has the excellent advantage of not only significantly improving line usage efficiency, but also increasing the reliability of relay transmission by using other channels as an alternative and continuing relay transmission even in the event of a failure of a particular channel or line. have

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the facsimile storage and forwarding system according to the present invention, and FIG. 2 is a flowchart showing an example of data relay transmission operation in the facsimile storage and forwarding system shown in FIG. IA, 1B...Storage and forwarding device, 2A,..., 2N.
...Facsimile terminal, 3...Line network, IOA, 10
B...Communication control unit, 11A, 11B...Central control unit, 12A, 12B...Storage unit, 1O-IA, 1O-2
A, +, 1O-nA, 10-18.10-28°...
, 1O-nB...Channel Figure 2

Claims (1)

[Scope of Claims] In a relay transmission system in a facsimile store and forward network in which data sent from a transmitting terminal is delivered to a receiving terminal via a transmitting storing and forwarding device and a receiving storing and forwarding device, the transmitting storing and forwarding device comprises: and the receiving side storage and forwarding device is
The transmitting storage and forwarding device selects one channel from among the plurality of channels and relays the data to the receiving storage and forwarding device. A relay transmission system in a facsimile store-and-forward network characterized by the following.