JPH0787087A - Multiple address communication system - Google Patents

Abstract

PURPOSE:To provide the multiple address communication system realizing multiple address communication of information efficiently in a short time. CONSTITUTION:A terminal equipment at a receiver side discriminates the validity of each information block to be sent by using a validity discrimination part 113 and a terminal equipment of a sender side selects a proper re- transmission system with respect to the receiver side terminal equipment among plural re-transmission systems based on the result of discrimination collected by a discrimination result collection part 115 collecting the discrimination result by the validity discrimination part 113 and sends again the information block discriminated to be invalid by the validity discrimination part 113 according to the selected re-transmission system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast communication system, and in particular, it divides the same information from a transmitting side terminal to a plurality of receiving side terminals into one or more information blocks and transmits them via a communication network. The present invention relates to a broadcast communication system for transmitting.

[0002]

2. Description of the Related Art The prior art will be described below.

In a communication system in which a plurality of nodes are connected in a loop as shown in FIG. 7, each slave node 72a, from a master node 71 via a transmission line 73,
A node control program may be transmitted to 72b, 72c, 72d, and 72e.

Further, in a system for accumulating various kinds of information such as a moving image as shown in FIG. 8 and providing the accumulated information in response to a user's request, the accumulated information is transmitted via a communication network 83. , An information providing service server 82 that directly responds to a request from a user from the information supply server 81.
a, 82b, 82c, 82d, 82e, 82f, 82g
May be delivered to. In these cases, since the information to be communicated is digitized information, if there is a discrepancy between the information transmission source and the information transmission destination, the operation of the system is adversely affected.

As described above, when the same information is accurately transmitted from a terminal to a plurality of terminals, such as a local area network typified by IEEE802.3, which shares a transmission path and has a broadcast address, can be simultaneously transmitted. In the case of a communication system in which broadcast communication is relatively easy, it is possible to transmit to a plurality of terminals at the same time, but it is very difficult to confirm the validity of the information from all the destination terminals. But,
If the information is not confirmed to be legitimate, the information will lack legitimacy.

In the case of a communication system such as a telephone network in which simultaneous broadcast communication is difficult, information is transmitted individually, and while confirming the correctness of the information for each information block, after the transmission to one terminal is completed, another terminal is transmitted. Therefore, the time for transmitting information to the entire system increases every time the number of terminals increases.

Further, like an asynchronous transfer mode communication network,
In some cases, the loss of information blocks in the communication network, that is, the discarding of cells is permitted.

[0008]

As described above, conventionally, in a communication network, since the contents of an information block are erroneously transmitted or the information block itself disappears, the validity of the transmitted information is confirmed by the terminal. It was very important to check between them. However, when the same information is simultaneously transmitted to a large number of terminals, it takes a lot of time to confirm the validity of the transmitted information to all the destination terminals.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a broadcast communication system that efficiently broadcasts information in a short time.

[0010]

SUMMARY OF THE INVENTION The present invention is a broadcast communication system in which the same information is divided into one or more information blocks from a transmission side terminal to a plurality of reception side terminals and transmitted via a communication network. In the above, the terminal on the receiving side includes a discriminating means for discriminating the validity of each transmitted information block, and the terminal on the transmitting side collects the discrimination result by the discriminating means. A retransmission method selecting means for selecting an appropriate retransmission method for the receiving terminal from a plurality of retransmission methods based on the discrimination result collected by the discrimination result collecting means, and a retransmission selected by the retransmission method selecting means Retransmission means for retransmitting the information block determined to be invalid by the determination means according to the method.

[0011]

In the present invention, the receiving side terminal determines the validity of each information block transmitted by the determining means, and the transmitting side terminal collects the determination result by the determining means. Based on the discrimination result collected by the collection means, an appropriate retransmission scheme for the receiving terminal is selected from a plurality of retransmission schemes, and the information block determined by the discrimination means to be invalid according to this retransmission scheme is retransmitted.

[0012]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of an embodiment of the broadcast communication system of the present invention.

In FIG. 1, the terminal 1 is connected to a communication network 16 by a communication path 15, and communicates with other terminals via the communication network 16. In addition, the terminal 1 includes a terminal control unit 11,
The communication control unit 12, the information storage unit 13, and the received information block validity determination result table 14 are included.

The terminal control unit 11 controls the terminal device 1 as a whole and controls the transmission in the broadcast communication, the transmission control unit 111 that controls the reception in the broadcast communication, and the validity of the received information. Correctness discriminating unit 1 for discriminating sex
13. Discrimination result setting unit 11 that sets the result of discrimination of validity in the reception information block validity discrimination result table 14.
4, a discrimination result collection unit 115 that collects the legitimacy discrimination results,
It has a retransmission method selection unit 116 that selects a retransmission method based on the collected correctness determination result.

Under the control of the terminal control unit 11, the communication control unit 12 communicates with other terminals via the communication network 16.

The information storage unit 13 stores information transmitted and received by the terminal 1.

The received information block validity determination result table 14 stores the validity determination results. Next, the operation of the broadcast communication system thus configured will be described.

FIG. 2 is a flow chart showing the operation of the transmitting side terminal when performing broadcast communication. When an information broadcast transmission interrupt occurs in the transmission side terminal (step 21), one information block of information to be transmitted is transmitted by broadcast (step 22). The information blocks are sequentially transmitted until a fixed time has elapsed, and when the fixed time has elapsed (step 23), the transmitting side terminal collects the received information block correctness determination result of each receiving side terminal (step 24). Based on the collected result, it is judged whether the retransmission is necessary (step 2
5) If resending is necessary, is the method of resending the information block to the receiving terminal used when the information blocks determined to be invalid are concentrated on the specific terminal (step 2)
7) Is it a method of re-broadcasting the information block to all terminals used when the information block determined to be invalid is distributed to the terminals of a predetermined ratio or more (step 28),
Or a retransmission method that combines these (step 2
9) is selected (step 26).

In FIG. 2, each information block is transmitted once, and the validity determination result is collected after a certain time has passed. However, after transmitting a certain number of information blocks once,
Alternatively, the correctness determination result may be collected after repeatedly transmitting a certain number of information blocks for a certain period of time.

FIG. 3 is a flow chart showing the operation of the transmitting side terminal when the information block which is not normally received is retransmitted for each receiving side terminal as shown in step 27 of FIG.

From the receiving side terminal, the terminal of the retransmission destination is determined (step 32), the information block to be retransmitted is determined from the received information block validity judgment result of the terminal of the retransmission destination (step 33), and this retransmission is to be performed. The information block is transmitted (step 34). Each time an information block is transmitted, the legitimacy of the information block is confirmed (step 35), and it is judged whether this confirmation result is legitimate or not (step 36). If it is not legitimate, transmission and confirmation of the retransmitted information block is confirmed. Is repeated (steps 34 and 35). If justified,
It is judged whether or not there is an information block to be retransmitted to the terminal (step 37), and the next information block is transmitted (steps 33, 34, 35 and 36). If the transmission of the information block to the terminal is completed, it is judged whether there is a terminal to be retransmitted (step 38), and if there is a terminal to be retransmitted, the information block is retransmitted to the next terminal (step 32). , 33, 34, 35,
36, 37).

FIG. 4 is a flow chart showing the operation of the transmitting side terminal when the information block which has not been normally received is retransmitted by re-broadcasting as shown in step 28 of FIG.

When an information block re-broadcast execution interrupt occurs (step 41), the information block to be re-broadcast is determined based on the result of collecting the received information block correctness determination result (step 42). Broadcast again (step 43). It is judged whether or not there is information to be rebroadcast (step 44), and if there is information to be rebroadcast, rebroadcast of the information block is repeated (steps 42 and 43).

FIG. 5 shows a case in which the information block that has not been normally received is retransmitted by combining the method of re-broadcasting as shown in step 29 of FIG. 2 and the method of retransmitting each receiving terminal individually. It is a flow chart which shows operation of a side terminal.

When a combined retransmission execution interrupt is generated (step 51), it is judged whether there is an information block to be re-broadcast based on the result of collecting the received information block correctness discrimination results (step 52), and re-broadcasting is performed. If there is an information block to be broadcast, after re-broadcasting the information block (step 53), the information block is retransmitted for each receiving terminal (step 54). If there is no information block to be broadcast, the receiving terminal Only the information block for each individual is retransmitted (step 54).

In addition, as a result of collecting the correctness determination results, when the normal reception rate of the information blocks is less than a certain value, all the information blocks are broadcast again, and thereafter, the receiving terminals are normally operated individually. Send an information block that has not been received. Alternatively, a retransmission method may be used in which all the information blocks are broadcast again, and after the normal reception rate of the information blocks reaches a certain level or more, the information blocks that have not been normally received are transmitted individually to the receiving terminals. At this time, the basis for selecting the retransmission method based on the result of collecting the correctness determination results is not particularly limited.

FIG. 6 is a flow chart showing the operation of the receiving side terminal when performing the broadcast communication. When a reception interrupt occurs in the receiving terminal (step 601), the arrived information block is received (step 602), and first, it is determined whether the received information block is a request for collecting the correctness determination result (step 603). If it is a request for collecting the validity determination result, the contents of the reception block validity determination result table 14 of the own terminal is transmitted to the terminal on the transmitting side that has issued the request for collecting the validity determination result (step 604). Next, it is judged whether the received information block is the broadcast information block (step 60).
5) If it is a broadcast information block, the legitimacy of this information block is determined, and if it is legitimate, this information block is stored in the information storage unit 13 (step 608). Further, the determination result of the validity of the information block is set in the received information block validity determination result table 14 (step 609). Next, when it is determined in step 605 that the received information block is not the broadcast information block, it is determined whether the received information block is the re-broadcast information block (step 60).
6) If it is the re-broadcast information block, it is judged whether or not the information block is an information block to be received by the terminal (step 607), and if it is the information block to be received, the broadcast information is received. Similar to the block, the validity of the information block is determined, the information block is accumulated, and the received information block validity determination result table 14 is set (step 6).
08,609). Next, when it is determined in step 606 that the received information block is not the re-broadcast information block, it is determined whether this received information block is the individual retransmission information block (step 610), and when it is the individual retransmission information block, the information is While determining the legitimacy of the block, the information block is stored in the information storage unit 13 (step 611),
The validity determination result of this information block is transmitted to the transmission source of the information block (step 612).

The correctness determination result collection may be performed by a part of the receiving side terminals, the reception status of all the receiving side terminals may be estimated from this result, and the retransmission method may be selected.

Further, not only when the contents of the information block are erroneously transmitted but also when the information block itself disappears as in an asynchronous transfer mode communication network, it is determined that the information is not valid. Further, in order to detect the disappearance of the information blocks, the terminal side also recognizes the order of the information blocks, rearranges the received information blocks in the correct order, and stores them in the information storage unit 13.

[0031]

As described above, according to the broadcast communication system of the present invention, when the same information is simultaneously transmitted from the information source terminal to a plurality of terminals, the information to be transmitted is divided into blocks. However, based on the validity judgment result of the information received by the receiving terminal for a certain period of time or for each certain number of information blocks, the method of attempting retransmission by transmitting the information block to each receiving terminal individually, the information block by broadcast Is sent or a combination of these is sent to try the retransmission, the retransmission method is selected and the information block that was not transmitted normally is retransmitted. Rather than transmitting information while confirming the correctness of information individually for each of multiple terminals, information blocks are transmitted and the correctness of information is confirmed. Number of certification is reduced, it is possible to realize a broadcast in a short time efficiently information.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a broadcast communication system of the present invention.

FIG. 2 is a flowchart showing an operation of the transmission side terminal when the transmission side terminal according to FIG. 1 is performed.

FIG. 3 is a flowchart showing an operation of a transmitting side terminal in the case of retransmitting an information block for each receiving side terminal that is not normally received according to FIG.

FIG. 4 is a flowchart showing an operation of a transmitting side terminal when retransmitting an information block which has not been normally received according to FIG. 1 by rebroadcasting.

FIG. 5 is a flowchart showing an operation of a transmitting side terminal in the case of performing retransmission by combining a method of rebroadcasting an information block which is not normally received according to FIG. 1 and a method of individually retransmitting the receiving terminal.

FIG. 6 is a flowchart showing an operation of a receiving side terminal when performing broadcast communication according to FIG.

FIG. 7 is a diagram for explaining a conventional communication system in which a plurality of nodes are connected in a loop.

FIG. 8 is a diagram for explaining a conventional system for accumulating various kinds of information such as moving images and providing the accumulated information in response to a user's request.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 terminal 11 terminal control unit 111 transmission 112 reception control unit 113 correctness determination unit 114 determination result setting unit 115 determination result collection unit 116 retransmission method selection unit 12 communication control unit 13 information storage unit 14 reception information block validity determination result table 15 Communication channel 16 Communication network

Claims (3)

[Claims] 1. A broadcast communication system for transmitting the same information from a transmitting side terminal to a plurality of receiving side terminals by dividing it into one or more information blocks through a communication network, wherein the receiving side terminal is , A discrimination means for discriminating the legitimacy of each transmitted information block, wherein the terminal on the transmission side comprises a discrimination result collecting means for collecting discrimination results by the discrimination means, and a discrimination result collecting means. Retransmission method selection means for selecting an appropriate retransmission method for the receiving terminal from among a plurality of retransmission methods based on the collected discrimination results, and the discrimination means is not valid according to the retransmission method selected by the retransmission method selection means A broadcast communication system, comprising: a retransmitting unit that retransmits the information block determined to be. 2. The broadcast communication according to claim 1, wherein the discrimination result collecting means collects the discrimination result at a constant time interval, a constant information block count, or a combination thereof. system. 3. The re-transmission method selecting means re-transmits to the terminal when the information blocks, which have been judged to be invalid, are concentrated in a specific terminal, and the method is judged to be invalid. 2. The broadcast communication according to claim 1, wherein when the information blocks are distributed to a certain ratio of terminals or more, a method of retransmitting to all terminals and a method of retransmitting by a combination of these are selected. system.