JPS6286943A - Loop network system - Google Patents

Abstract

PURPOSE:To establish a communication channel between nodes easily when one side communication function of a communication station is stopped due to fault of a transmission line of fault of the communication station itself, by setting a specific address corresponding to above-mentioned left and right transmission lines in an address holding circuit to communication function of normal side. CONSTITUTION:When fault occurred in a system, an input signal to a node is outputted to the transmission line from a transmission line opposite to the transmission line in which fault is detected, and a transmission line change-over switch 35 is controlled to make return output to above-mentioned transmission line to form a loop back. At this time, two specific addresses corresponding to left and right transmission lines are set to normal side transmission line. For instance, in a node 3, a former address is set to an address holding circuit 60 and the same address with 62, 63 is set to an address holding circuit 61. Nodes 2 and 3 are made to have two addresses, and communication between nodes is realized even when nodes 1, 4 make address corresponding to left and right transmission lines of nodes 2 and 3 a destination.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to RAS control of loop networks.

BACKGROUND OF THE INVENTION FIG. 2 shows a general configuration of a loop network system. Each communication station (hereinafter referred to as a node) 1.2, 3.4 has two loop-shaped transmission lines 101 on the left and right.
, 102, and various information processing devices (hereinafter referred to as terminals) 11 to 15 connected to each node can send and receive information to and from each other via the loop network system.

Figure 3 shows the configuration of the node. The node is left and right transmission path 10
It is composed of two pairs of optical repeaters 31, 32, two pairs of player signal j order control units 33, 34, and one transmission level crossing switch 35 so that transmission and reception can be performed by using 1 and 102 at the same time. The communication procedure control unit includes path control units 40, 41 . Transmitting units 42, 43 that control the transmission of data to the transmission path, receiving units 44, 45 that receive data from the transmission path, buffers 746, 47 that store transmitted and received data, address holding units 48, 49 that hold addresses, and It consists of a control section 50.51 that controls the communication function, a system monitoring section 54, 55 that detects data on the transmission path, and a system control section 56.57 that controls failure processing for these, and an address holding section 48.
49 is set with the same address that is unique to the node.

In such a loop network system, the fourth
When the transmission path failure shown in the figure occurs, the nodes 2 and 3 that are affected by the failure will stop outputting to the transmission path on the side where their system monitoring units 54 and 65 have detected data loss, and The input signal from the opposite transmission path to the node is output to that transmission path, forming a loopback and repairing the fault as shown in Figure 6 (for example, Ohno et al., ``RAS Control Method in Optical Loop Network System'') 1985 National Conference of the Institute of Electronics and Communication Engineers (1812).

Problems to be Solved by the Invention As mentioned above, the fault can be repaired, but in the loop mode, nodes 1 and 4 are connected to both the left and right transmission paths, and the same connection is applied to the left and right transmission paths. Because it has an address, multiple communication paths between nodes will be set up.
2M receives data sent by another node. In order to solve these problems, when a failure occurs, complicated control is required, such as connecting each node to either the left or right transmission path.

In order to solve the above-mentioned problems, even if a failure occurs and the connection form between the nodes and the transmission path changes, the present invention maintains a logical communication path between the nodes. Each of the communication stations has an address holding circuit that can set two or more addresses, and normally unique addresses are set for the left and right transmission paths in the address holding circuits, and the communication station When the communication function on one side is stopped due to a failure, one unique address corresponding to the left and right transmission paths is set in the address holding circuit for the communication function on the normal side.

According to the present invention, with the above configuration, even if the communication function of one side of the node stops due to a transmission path failure or a failure of the communication station itself, both addresses corresponding to the left and right transmission paths are set in each node, Communication paths between nodes can be easily established.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. Configuration of loop network system.

The diagrams showing the locations where the failure occurs are the same as those in FIGS. 2, 4, and 6 shown in the prior art, so the same numbers are given and some explanations are omitted.

Figure 1 shows the configuration of the node. Note that the same components as those in the example shown in the prior art are given the same numbers and explanations will be omitted.

Each node has an address holding circuit 50, 61, 62, 6, which can set two addresses for the left and right transmission paths.
3 will be provided. If the communication function of the node is normal, unique addresses are set for the left and right transmission paths in the address holding circuits 60, 61, 62, and 63, the same address is set for 6Q and 61, and the same address is set for 62.63. The same address different from 60.61 is set. Although there are various methods of assigning addresses and the number of address holding circuits, they are not essentially related to the present invention.

When a failure as shown in Figure 4 occurs in such a system, the input signal to the node from the transmission line opposite to the transmission line where the failure was detected is output to that transmission line, and the signal is looped back and output to the transmission line. The line feed path changeover switch 36 is controlled so that a loopback as shown in FIG. 57 is formed. At this time, two unique addresses corresponding to the left and right transmission paths are set for the normal book transmission path. For example, in the node 3, the previous address is set in the address holding circuit 6o, and the same address as 62°63 is set in the address holding circuit 61. At this time, nodes 2 and 3 are
Having two addresses, communication between the nodes is realized even if nodes 1 and 4 use addresses corresponding to the left and right transmission paths of nodes 2 and 3 as destinations. Also, nodes 1 and 4
Since it has two addresses, for example, data sent from Ishiki of node 1 will not be received by node 1 in the left system, and data sent by other nodes will not be received twice.

Effects of the Invention As described above, according to the present invention, even if the connection state between the nodes and the transmission path changes due to fault repair, it is possible to easily establish the communication path between the nodes.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a node configuration according to the present invention, FIG. 2 is a diagram showing a general configuration of a loop network system, FIG. 3 is a diagram showing an example of a conventional node configuration, FIG. 4 and FIG. 6 are diagrams showing a fault state and a fault repaired state of a loop network system according to an embodiment of the present invention. 1-4...Node, 11-16...Terminal, 31-32...Optical repeater, 33-34...
...Communication procedure control unit, 36...Transmission path changeover switch, 48°49...Address holding circuit, 60-61...Communication control unit, 60.61 .6
2.63...Address holding circuit, 101...
...Clockwise transmission line, 102...Counterclockwise transmission line. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure? I for 1 person; 1 % I
Figure 2/l Figure 3 1 Mei procedure controller b Generalization procedure control l Figure 4 Figure 5

Claims (1)

[Claims] A clockwise loop transmission path in which signals propagate clockwise through a communication station that controls data access to the transmission path, and a counterclockwise loop transmission path in which signals propagate counterclockwise, using both loop transmission paths. A loop network is formed by a plurality of communication stations that communicate with each other, and each of the communication stations has an address holding circuit that can set two or more addresses for the left and right transmission paths, and usually the address holding circuit Unique addresses are set in the circuit for the left and right transmission paths, and when the communication station stops the communication function on one side due to a transmission line failure or a failure in the communication station itself, the above-mentioned address is set for the communication function on the normal side. A loop network system characterized by setting two unique addresses corresponding to left and right transmission paths in an address holding circuit.