JPH03124142A - Multiple address communication system - Google Patents

Abstract

PURPOSE:To easily attain multiple address communication without addition of a special circuit to a switch by providing a specific label used at multiple address communication in a star LAN and feeding an information block with label for multiple address communication sequentially between terminal equipments connecting to the LAN. CONSTITUTION:Terminal equipments 21-24 in a star LAN are connected to a center switch 1 with incoming lines 31-34 from the terminal equipments to the switch and outgoing lines 41-44 from the switch to the terminal equipments and data transmission reception is implemented between terminal equipments via the center switch 1. When the terminal equipments 21-24 receive an information block with a specific label added thereto, the received information block is again sent. On the other hand, when a specific label is received from a terminal equipment by the center switch 1, the predetermined terminal equipment is switched. A terminal equipment to receive a data succeedingly is decided to pass through all opposite terminal equipments to which the information block is desired to be sent without fail. Thus, multiple address communication is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a broadcast communication system in a star LAN for exchanging label-multiplexed information blocks.

(Prior art) When implementing a broadcast communication system in a conventional star-type LAN, it is necessary to use the method described in 1988 IEICE Autumn National Conference Paper 5B-4-3rA Study on ATM Switch Architecture. In addition, one broadcast communication was realized by installing dedicated hardware for broadcast communication in the switch at the center.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, dedicated hardware for broadcast communication was required in the switch, and control was also complicated. Furthermore, since there is no repeatability within the switch configuration,
The hardware was also unsuitable for converting switches to LSI.

An object of the present invention is to provide a system that enables broadcast communication without using dedicated hardware for broadcast communication on the switch side.

[Means to solve the problem]

In order to achieve the above purpose, when the terminal side receives an information block with a specific label attached, there is a means for retransmitting the information block, and a switch side has a means for retransmitting the information block with the specific label received from the terminal. For information blocks,
It is provided with means for switching to a predetermined terminal.

[Effect]

When a terminal receives an information block to which a specific label is attached, it transmits the received information block again. On the other hand, when a switch receives a specific label from a terminal, it switches to a predetermined terminal. Broadcast communication becomes possible by determining the next terminal to send the information block so that it always passes through all the destination terminals to which the information block is to be sent.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a star-type LAN that implements the broadcast communication system of the present invention. The terminals 21 to 24 are connected to the center switch 1 by uplinks 31 to 34 from the terminals to the switches and downlinks 41 to 44 from the switches to the terminals, and data can be sent and received between the terminals via this center switch. conduct.

Next, the operation inside the terminal will be explained using FIG. FIG. 2 shows an example of the configuration of the data transmitting/receiving section 211 in the terminal. On the data transmitting side, a transmission buffer 2111. A selector 2113 that selects information blocks in the retransmission buffer 2112, transmission buffer 2111, and retransmission buffer 2112 that temporarily stores information blocks with specific labels added for broadcast communication.
, a transmission control circuit 2114. On the data receiving side, a receive buffer 2116. which temporarily stores received information blocks from the downlink 41. Monitor the label of the received information block,
It consists of a label detection circuit 2115 that opens an AND gate 2117 and controls writing of the information block to a retransmission buffer 2112 in the case of a specific label.

Next, the operation of the terminal when receiving a specific labeled information block will be explained. When the information block enters the data transmitting/receiving unit 211 from the downlink 41, it is written into the receiving buffer 2116 like other information blocks. On the other hand, the label detection circuit detects that the information block has a specific label and opens the AND gate 2117.
The information block is also written to the retransmission buffer 2112. The information block written in the retransmission buffer is sent to the selector 21 under the control of the transmission control circuit 2114.
13 and is transmitted to the uplink 31. In this way, when the specific labeled information block is received by the terminal, it is transmitted again to the uplink as is.

The operation of the switch will be explained using FIG. The switch 1 includes routing information adding circuits 111 to 114 . which exist for each uplink and adds routing information to an information block from a terminal. routing tables 121 to 124 connected to the routing information adding circuit and storing routing information corresponding to labels of information blocks;
The self-routing switch 10 switches the information block based on the routing information added to the information block.

Next, the operation of this switch will be explained. Switch 1 uses the routing table to search for routing information from the label of the information block sent from the terminal,
This routing information is added to the beginning of the information block, and this routing information is used to autonomously switch and carry the information block to the destination line. number, and the specific label used by the terminal 21 for broadcast communication is "11".
”. In this case, the routing tables 121-1
The value shown in FIG. 3 is stored in advance at the location marked with "11" in 24.

When an information block with a specific label "11" is input to the switch 1 from the terminal 21, the routing information adding circuit 111 searches the routing table 121 and adds the information block 312 to which the obtained routing information 1#42pt is added. The signal is sent to the self-routing switch 10. The self-routing switch 10 performs switching based on the routing information "42" and sends the information block to the downlink 42 on the output side. Switch information blocks from all terminals in this way.

In the case of an information block with a specific label for broadcast communication "11", the values of each routing table 121 to 124 are set so that the information block is sent to all terminals, so from terminal 21 to terminal 22 → terminal 23→terminal 24, returns to terminal 21, and is discarded at terminal 21. or,
When performing broadcast communication from the terminals 22 to 24, it is possible to similarly perform broadcast communication by providing a specific label for each terminal.

In this embodiment, we have described the case where the specific label for broadcast communication is different for each terminal, but even if a common label value is set for all terminals, the information identifying which terminal started the transmission will not be able to be used. By adding this, it is possible to perform broadcast communication using a similar method. Furthermore, in this embodiment, a case was explained in which broadcast communication is performed to all terminals, but according to the present invention, a specific label is defined only for a group of terminals included in a certain group, and an information block within that group is defined. It can be seen that broadcast communication within any group can be easily performed by setting the routing table to transfer the .

〔Effect of the invention〕

According to the present invention, even in a star-type LAN, broadcast communication is easily possible without adding a special circuit to the switch. Furthermore, broadcast communication within any terminal group within a LAN can be easily realized using exactly the same method.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a star-type LAN according to an embodiment of the present invention, FIG. 2 is an embodiment of the terminal shown in FIG. 1 for realizing the present invention, and FIG. 1 is an embodiment of the switch shown in the figure for realizing the present invention. 221... Data transmission/reception unit, 2111... Transmission buffer, 2112... Retransmission buffer, 2113... Selector, 2114... Transmission control circuit, 2115...
Label detection circuit, 2116...Reception buffer, 10.
・Self-routing type switch, 111-114...
・Routing information addition circuit, 121-124...Jun 2 of the routing table drawing (no 2nd change in content) 61 mouth / -2>7-Suidate 21-24-
---Sauki 31-34-----, Hiri c3 41-d4----Second 9th Ensho (relationship with the case of the person making seven amendments)

Claims (1)

[Claims] 1. In a star-type LAN that exchanges label-multiplexed information blocks, a specific label for use in broadcast communication is provided, and the label for broadcast communication is added to a terminal connected to the LAN. means for retransmitting the information block when the information block is received, the switch used in the LAN switches the labeled information block for broadcast communication transmitted from the terminal to the next determined terminal; A broadcast communication system characterized by providing a means for transmitting labeled information blocks for broadcast communication between terminals in sequence. 2. In a star-type LAN that exchanges label-multiplexed information blocks, a specific label used during broadcast communication is provided, and a terminal connected to the LAN receives the information block to which the label for broadcast communication is attached, means for transmitting the information block to the data transmission line when data is received from the data reception line; a switch used in the LAN determines the labeled information block for broadcast communication to be transmitted from the terminal; A broadcast communication system characterized by providing means for switching to the next terminal and sequentially sending labeled information blocks for broadcast communication between terminals. 3. The broadcast communication system according to claim 1, wherein the information block has a fixed length. 4. The broadcast communication system according to claim 1, wherein a specific label used for broadcast communication is made common to all terminals within the LAN. 5. The broadcast communication system according to claim 1, wherein a specific label used for broadcast communication is provided for each terminal or for each group of terminals within the LAN. 6. The broadcast communication system according to claim 3, wherein the switch is a self-routing ATM switch configured as a switch matrix network.