JPH0311592B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a message retransmission system from a storage device to a terminal in message storage communication.

Message storage communication, in which user messages sent from a sending terminal, such as messages in facsimile communication, are temporarily stored in a storage device and then sent to a receiving terminal, can be used for broadcast communication, confidential communication, etc., which was not possible with instant communication. It enabled new message communication services such as mailbox service.

Conventionally, in this type of message storage communication, when a user message is transmitted from a sending terminal and stored in a storage device by taking advantage of the storage communication, and is sent from the storage device to a receiving terminal, the receiving terminal is in use or has a problem, etc. If it is determined that reception is not possible for this reason, transmission is automatically (uniformly) retried N times (retransmission) at time T.

Furthermore, if the user message cannot be sent even with such retransmission, it is determined that the user message has not been delivered, and the storage device, for example, in the case of facsimile communication, creates a non-delivery notification in the form of a message by itself and sends it. A notification to that effect was sent to the terminal.

However, if retransmission is performed with T set to 10 hours and N set to 5 times, for example, and the message is not delivered, the sending terminal will receive a non-delivery notification after about 10 hours have passed since the message was sent. It is not until the message is returned that it is known that the message was not delivered to the receiving terminal. Therefore, when a message is highly urgent and requires immediacy, automatically retransmitting it when it cannot be delivered to the receiving terminal has the problem of deteriorating the service quality for the user. There is.

In other words, if the content of the message is highly urgent, retransmission is rather unnecessary, and the message is immediately delivered to the sending terminal when it is determined that it is undeliverable at the time of the first delivery to the receiving terminal. If the user is notified of the undeliverability, the user can take measures such as conveying the requirements of the sending terminal using an instant communication method such as a telephone instead of sending the message. Immediate notification is better for service. However, if retransmission is not performed at all, there is a problem that in such message storage communication, there is a high probability that the message will be undelivered, and the advantages of storage communication will not be utilized.

In order to solve these problems, the present invention has the following features:
When it is determined that the user message cannot be delivered at the first delivery opportunity from the storage device to the receiving terminal, the sending terminal is immediately notified of this, and the storage device retransmits the user message according to the instructions of the sending terminal. By performing control or discarding the user's message, it is possible to take advantage of the advantages of message storage and communication while improving service to the user, and will be explained in detail below with reference to the drawings.

FIG. 1 shows an example of a network configuration for explaining the present invention, and shows an example of center-end type facsimile communication.

In the figure, 1 is an information center, 2 is a facsimile terminal, 3 is an exchange that accommodates the information center 1, 4 is an exchange that accommodates the facsimile terminal 2, 5 is a storage device connected to the exchange 3, and 6 is connected to the exchange 4. It is a storage device where

2 and 3 are embodiments of the present invention showing the signal sequences between the devices shown in FIG. Indicate the case.

When information center 1 makes a call, information center 1
A path setting request and the destination terminal (facsimile terminal 2) number are transferred to the storage device 5 by a two-end general communication request command.

When the request is approved, the storage device 5 sends a signal (+RSP) to the information center 1 and a path is established.
After setting the path, the information center 1 transmits, for example, one page of the message, and the storage device 5 stores the message and disconnects the path.

Further, the storage device 5 selects the destination storage device 6 based on the destination terminal number, and after setting the path, transfers the stored message to the storage device 6 and disconnects the path.

Once the storage device 6 stores the message, it requests the exchange 4 to set up a path to the facsimile terminal 2, but if it determines that the facsimile terminal 2 is unable to communicate due to a failure or the like, a negative response is sent back to the storage device 6.

In this case, the storage device 6 does not retry transmitting the message to the facsimile terminal 2, but the information center 1 determines whether to retransmit the message or discard the message and interrupt delivery. An inquiry request signal (ASK) is immediately transmitted to the storage device 5 in order to make an inquiry.

Upon receiving the inquiry request signal, the storage device 5 immediately transmits an inquiry command (INQ) to the information center 1.

Information center 1 uses its inquiry command (INQ)
, it is recognized that the sent message could not be delivered to facsimile terminal 2, and a retransmission instruction is given depending on the content of the message (interruption: DIS, continuation: CON).
is returned to the storage device 5. Storage device 5 immediately transmits this retransmission instruction to storage device 6.

When the storage device 6 receives an interruption instruction from the storage device 5, it discards the communication, interrupts the delivery, creates an interruption notice and sends it back to the storage device 5, and sends it back to the storage device 5.
further sends the notification text back to the information center 1.

When a continuation instruction is received from the storage device 5, the message retransmission timer of the storage device 6 is started, and when the operating time t becomes tt _s with respect to the retransmission interval _ts , the facsimile terminal is sent to the exchange 4 again. 2, and if the message cannot be delivered because the path cannot be set, etc., the timer for retransmitting the message is set again.
Start _TS and try retransmission.

If the message cannot be delivered even after trying to retransmit it N times (N×t _s T) within T time from the initial path setting request time, it is determined that the message has not been delivered, and the storage device 6 creates a non-delivery notification message. and returns it to the storage device 5.
further sends the non-delivery notification to the information center 1.

Note that each value is determined so that N×t _s T in retransmission, but the retransmission interval t _s does not necessarily have to be the same each time.

FIG. 4 is an embodiment diagram showing the configuration of the storage device 6 used in the present invention, in which 10 is a central control device;
1 is an interface device that controls communication with the storage device 5; 12 is a main memory; the retransmission time period T;
Functions such as the number of retransmissions N, a message retransmission timer T _S , a retransmission counter n, a retransmission instruction, and a retransmission interval are held; 13 is a disk device for storing messages, and 14 is a facsimile terminal via an exchange 4. This is an interface device that communicates with 2.

The central control unit 10 issues a path setting request to the exchange 4 via the interface device 14 for delivering the accumulated messages to the facsimile terminal 2, and also starts the timer T _S in the main memory 12 to set the retransmission counter. Set n to 1. If a path setting completion notification is received from switch 4 in response to the path setting request,
The central controller 10 has a timer on the main memory 12.
T _S , the retransmission counter n is reset, and the message is delivered from the disk device 13 via the interface device 14 to the facsimile terminal 2 via the exchange 4, and after the delivery is completed, the path is disconnected.

However, when a negative response is returned to this path setting request, the central processing unit 10 inquires of the information center 1 whether to retransmit the message or discard the message and interrupt delivery. Therefore, an inquiry request signal (ASK) is immediately transmitted to the storage device 5 via the interface device 11.

However, since the retransmission instruction from information center 1 may be delayed for some reason, the timer T _S and counter n are set when the first message is delivered as described above, and the retransmission trigger is set before the retransmission instruction arrives. If so, retransmit will be performed.

The retransmission instruction from the storage device 5 is transferred to the main memory 12 via the interface device 11.
The central controller reads this retransmission instruction and if the retransmission instruction continues, timer T _S times out and t
Wait until t _s .

When the timer T _S times out and a retransmission opportunity comes, the central control unit 10 sets the path to the exchange 4 again, and also updates the timer T S in the main memory 12.
Activate T _S and increment the counter n by 1. Such retries are repeated, and when the value n of the counter n reaches nN, no further retries are performed and it is determined that the delivery has not arrived.

In case of non-delivery, the originating terminal (information center 1)
In order to notify the navel, the central control device 10 creates a non-delivery notification and stores the non-delivery notification in the storage device 5.
After setting a path via the interface device 11 and transferring the non-delivery notification, the path is disconnected and the series of processing is completed.

Next, if the retransmission instruction is an interruption, the central controller 10 immediately starts the timer on the main memory 12.
T _S , reset counter n, and disk device 1
In addition to discarding the messages accumulated in 3, an interruption notification message is created, a path is set to transfer the interruption notification message to the storage device 5 via the interface device 11, and the interruption notification message is transferred to the storage device 5. 5, the path is disconnected and the series of processing is completed.

Note that although the above example has been described in the case where an information center is used as a sending terminal and a facsimile terminal is used as a receiving terminal, the present invention is not limited to this.
It is clear that the present invention can also be applied to communication between other terminals used for message storage communication.

As described above, according to the present invention, the storage device 6
If it is determined that the user message cannot be delivered at the first delivery opportunity from the source terminal (for example, facsimile terminal 2) to the destination terminal (for example, facsimile terminal 2), the user's intention on the originating terminal (for example, information center 1) side (whether to continue retransmission or interrupt it) is determined. It becomes possible to process the user's message based on the following information, and has the advantage of improving serviceability while taking advantage of the merits of message storage and communication.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a network configuration for explaining the present invention, FIGS. 2 and 3 are diagrams showing an embodiment of the present invention showing signal sequences between each device shown in FIG. 1, FIG. 4 is an embodiment diagram showing the configuration of the storage device 6 used in the present invention. 1...Information center, 2...Facsimile terminal,
3... Switching machine that accommodates an information center, 4... Switching machine that accommodates facsimile terminals, 5... Switching machine 3
storage device connected to 6... storage device connected to exchange 4, 10... central control device, 11...
12... Main memory, 13... Disk device, 14... Interface device for communicating with the facsimile terminal 2 via the exchange 4.

Claims (1)

[Claims] 1. In message storage communication, in which a storage device is placed between a sending terminal and a receiving terminal via a communication path, messages from the sending terminal are stored in the storage device and then delivered to the receiving terminal. If it is determined that the message cannot be delivered at the time of delivery of the first message to the terminal,
The storage device notifies the sending terminal to that effect and requests instructions on whether to continue or interrupt the delivery.
An adaptive retransmission system characterized by controlling message retransmission when the instruction from the sending terminal is to continue, and discarding the message when the instruction is to discontinue.