JPH039637A - Multiple address communication method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding a broadcast communication method in a mesh-like network, when broadcast communication is performed in a mesh-like network,
The purpose of this is to provide a broadcast communication method that can shorten the residence time of communication frames after broadcast communication is completed.In order to provide a broadcast communication method that can shorten the residence time of communication frames after broadcast communication is completed, a relay node number area is provided in the communication frame transmitted by each node to write the number of relay nodes, and each The node includes a node number writing means that writes the total number of nodes in the network into the relay node number area when sending a communication frame to the communication line for broadcast communication, and a node number writing means when the communication frame is received. , a decrementing means for decrementing the value of the relay node number field of the communication frame by one, and if the value decreased by the decrementing means is "0", the communication frame is discarded, and if it is other than "0", the communication frame is discarded. The configuration includes a transmitting means for transmitting the communication frame to a connected communication line other than the received communication line.

[Industrial application field]

The present invention relates to a broadcast communication method in a mesh-like network in which a plurality of nodes are connected in a mesh-like manner through communication lines.

An example of a mesh-like network is shown in FIG. 7, in which nodes 1 and 6 are connected in a mesh-like manner through communication lines Ll to L9. For example, nodes 1, 2, and 3 are connected to communication lines LL, L2. A loop is formed by L3.

In mesh-like networks, loops exist as described above, but in such networks, broadcast communication (
(notifying all nodes of the same content), it is desirable that the residence time of the communication frame after the broadcast communication is completed is short.

[Conventional technology]

In a mesh-like network in which multiple nodes are connected in a mesh-like manner through communication lines, when a communication frame is sent out in a broadcast, a loop exists, so the communication frame is not discarded and goes round and round, forever. Broadcast communication in a mesh network has not been widely used because of the risk of stagnation and unnecessary network congestion in the network.

[Problem to be solved by the invention]

If the conventional technology is used to broadcast communication frames in a mesh network, there is a problem in that the communication frames remain forever, causing unnecessary network comparisons in the network.

An object of the present invention is to provide a broadcast communication method that can shorten the residence time of communication frames after broadcast communication is completed when broadcast communication is performed in a mesh network.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the present invention.

As shown in Figure 1, a relay node number area 10 is provided in the communication frame transmitted by each node to write the number of relay nodes, and each node is provided with a relay node number area 10 in which the number of relay nodes is written, and each node is provided with a relay node number area 10 in which the number of relay nodes is written. When a communication frame is received, the node number writing means 11 writes the total number of nodes in the network into the relay node number area 10, and when a communication frame is received, the value of the relay node number area 10 of the communication frame is set to one. Decrementing means 12, and if the value decremented by the decrementing means 12 is "0", the communication frame is discarded, and if it is other than "0°", the communication line connected to it is other than the communication line that received the communication frame. and a transmitting means 13 for transmitting the communication frame.

(Function) According to the present invention, when performing broadcast communication, the number of nodes writing means 11 is written in the number of relay nodes area 10 in the communication frame.
The total number of swords in the network is written and transmitted, and each time it passes through each node, the decrement means 12 decreases the value of the relay node number field 10 by 1, but the value of the field becomes "0". Until this happens, the communication frame must pass through all nodes in the network and broadcast communication is possible, and when it becomes "0'", the communication frame is discarded, so it stays in the network forever. Therefore, the residence time of communication frames after broadcast communication is completed can be shortened.

〔Example〕

FIG. 2 is a block diagram showing the configuration of a node according to an embodiment of the present invention, FIG. 3 is a flowchart of a transmission process according to an embodiment of the present invention, and FIG. 4 is a flowchart of a reception process according to an embodiment of the present invention. FIG. 5 is a diagram showing a communication frame format according to an embodiment of the present invention, and FIG. 6 is a diagram showing a network management table according to an embodiment of the present invention.

The configuration of each node is as shown in FIG. 2. Application software 20 requests data transmission for broadcast communication. When transmission data is sent from the application software 20, it is checked, and if it is normal, it calls the transmission processing section 22. Communication control section 21, transmission processing section 22 that performs transmission processing, reception processing section 23 that performs reception processing, network management table 2
4. It consists of a line control section 25 that performs line control.

The communication frame in this case, as shown in Fig. 5, includes a flag area (F), a transmitting station address, an address area indicating the destination station address (in the case of broadcast communication, this is considered as a broadcast), and a frame control information area. , a relay node number area 10, a data area, and a frame error control information (CRC etc.) area.

Further, as shown in FIG. 6, the network management table 24 stores, for example, 1. An area where when a response frame is received, it is assumed that it is not the first frame and is set to 0.
Area for setting the total number of nodes in the network, number of relay nodes, node address,
It has an area for writing line speed, line status, etc.

Here, the number of relay nodes for each node is the value obtained by subtracting the number of relay nodes in the received frame by one from the total number of nodes when the first frame addressed to its own node is received. Write when a frame is received.

Next, the transmission process will be explained with reference to FIG.

In step 1, when the application software 20 requests the communication control unit 21 to send data via broadcast, in step 2, the communication control unit 21 checks whether there is any abnormality in the data. If there is, abnormality processing is performed in step 3, and if there is no abnormality, the transmission processing section 22 is called.

Then, in step 4, the transmission processing unit 22 refers to the network management table 24, and in step 5, if the first frame is to be sent, indicates the first frame in the data area,
In step 6, the relay node number area 10 of the communication frame is
Set the total number of nodes to , and proceed to step 8.

If a response frame has been received and it is not the first frame, in step 7, the network management table 2 is
The maximum value of the number of relay nodes of each node of No. 4 is set in the number of relay nodes area IO of the communication frame, and the process proceeds to step 8.

In step 8, the transmission station address of the communication frame is set as the number of the own node, the destination station address is set as broadcast, and sent to the line control unit 25. In step 9, all connected lines 1, for example, in the case of node 1, Ll, L2 Send to.

Next, the reception process will be explained with reference to FIG.

For example, in the case of node 1, the line control unit 25
When a communication frame is received from 1, the reception processing unit 23
Notify that a communication frame has been received from the communication line L1.

In step 1, the reception processing unit 23 checks the communication frame for errors, and if there is an error, discards the communication frame, and if it is a normal frame, subtracts 1 from the value in the relay node number field 10 of the communication frame. , If the subtracted value becomes "0" in step 2, the communication frame is discarded in step 10.

In step 2, if the subtracted value is not "0," in step 3, the subtracted value is
The communication frame is sent to Step 2, and the process proceeds to Step 4.

In step 4, if a response is not required for the received communication frame, the process ends. If necessary, the process proceeds to step 5. If it is the first frame, in step 6,
The value obtained by subtracting one value from the number of relay nodes in the received frame from the total number of nodes, that is, the number of nodes that the communication frame passed + 1 (sending node), is used for relaying the response frame (the format is the same as the communication frame). Set in the number of nodes area, and also in the network management table 24.
Set the number of relay nodes of the transmitted node, and proceed to step 8.

If it is not the first frame in step 5, in step 7, the sending node's
Set the number of relay nodes to a certain value in the number of relay nodes area, and proceed to step 8.

In step 8, a response frame is sent out via the line control unit 25, with the partner station address set as the number of the node that sent the transmission, and the transmitting station address set as the own node number.

That is, at the time of the first frame, the value of the relay node number field of the communication frame is the total number of nodes in the network, but after receiving the response frame, the value of the relay node number field is less than the total number of nodes. Since this is the number of nodes for the node with the smallest number of relay nodes, the number of relay nodes to be passed through can be kept below this value, and the time spent on the network can be further shortened.

〔Effect of the invention〕

As explained in detail above, according to the present invention, when broadcast communication is performed in a mesh network, although some loops occur, the transmitted communication frame can always be removed, and the same This has the effect of shortening the residence time of communication frames on the network after the end of the communication, and reducing the occurrence of unnecessary network congestion.

[Brief explanation of drawings]

FIG. 1 is a diagram of the principle of the present invention, FIG. 2 is a block diagram showing the configuration of a node in an embodiment of the present invention, FIG. 3 is a flowchart of transmission processing in an embodiment of the present invention, and FIG. Flowchart of reception processing according to the embodiment; FIG. 5 is a diagram showing a communication frame format according to the embodiment of the present invention; FIG. 6 is a diagram showing a network management table according to the embodiment of the present invention; FIG. 7 is a diagram showing an example mesh FIG. 2 is a diagram showing the configuration of a network. In the figure, 1 to 6 are nodes, 10 is a relay node number area, 1 2 3 0 1 2 3 4 5 1 is a node number writing means, is a decrement means, is a transmission means, is application software, is a communication control unit, is is a transmission processing unit, is a reception processing unit, is a network management table, is a line control unit, and ~L9 indicates a communication line. Kidochi September's Gamande 1 Figure 1

Claims (1)

[Scope of Claims] In a mesh network in which a plurality of nodes are connected in a mesh shape through communication lines, a relay node number area (10) is provided in a communication frame transmitted by each node to write the number of relay nodes, Each node also includes a node number writing means (11) for writing the total number of nodes in the network into the relay node number area (10) when transmitting a communication frame to the communication line for broadcast communication. , when a communication frame is received, a decrement means (12) for decrementing the value of the relay node number field (10) of the communication frame by one, and the value decremented by the decrement means (12) is set to "0". If so, the communication frame is discarded, and if it is other than "0", the transmission means (13) is provided for transmitting the communication frame to a connected communication line other than the communication line that received the communication frame. Broadcast communication method.