JPH01221953A - Loop network constitution system - Google Patents

Abstract

PURPOSE:To rapidly shift control management to the one by a sub managing station by connecting a main managing station to the sub managing station by a blanching unit and a switch in parallel. CONSTITUTION:Optical blanching units 9 and 9' distribute the signals of a main system loop 4 and a sub system loop to the main managing station 1 and the sub managing station 2 equally, and optical switches 8 and 8' switch and connect those signals to the station on one side. When abnormality is generated in the station 1, the switches 8 and 8' selecting the station 1 select the station 2. In such a way, the signal of the loop 4 is transmitted to a transmission path of route 4'1 station 2 route 4'2 loop 4, and the signal of a loop 5 to the transmission path of route 5'1 station 2 route 5'2 loop 5, thereby, the station 2 can perform the control management for whole of the loop.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the improvement of a loop network that interconnects information devices distributed in factories, buildings, etc. to achieve OA efficiency. In particular, the present invention relates to a loop network configuration method that can avoid a major impact on the entire system when a problem occurs in a management station.

[Prior art] There are systems called star type and bus type for LAN, which connects multi-functional terminal equipment to form a network that can be controlled all at once. With the trend of increasing number of terminal devices connected to the Internet, loop networks with simple wiring have become mainstream these days.

In such a loop network, for example, as shown in FIG. 3, node stations 3a and 3b serve as input/output stations for terminal equipment (not shown).

3c and 3d are sequentially connected in a loop through a transmission line 4.5 made of optical fiber or the like. The above-mentioned transmission line has a duplex configuration, and consists of a main loop 4 running clockwise in the figure and a slave loop 5 running counterclockwise. In such a configuration, data transmission between terminals is performed using the main loop 4 during normal operation, and the slave loop 5 is used as a preliminary system to constantly send signals representing data such as "1". In the event that a station abnormality occurs, the standby system is used to perform a loopback to bypass the abnormal location, so that the entire system will not be shut down.

On the other hand, in the above loop network, there is a separate node station called a management station, which plays the role of supplying a transmission lock for the loop network, controlling the loopback described above, and monitoring each node station.

However, the management station performs management control of the entire system, and if an abnormality occurs in this management station, it will spread to the entire system, and the impact will be enormous. In order to avoid such a worst-case scenario, this management station usually has two stations, main management station 1 and sub-control station 2, with the same functions, as shown in Figure 3, and these are transmitted in a loop. connected in series to the
Then, as shown in Figure 3, if the main management station 1
If an abnormality occurs in the main management station 1, means are taken to cause the node stations that sandwich the main management station 1 to perform loopbacks 6 and 7, and to have the sub-pipeline station 2 take over all the roles that the main management station 1 was playing.

[Problems with the Prior Art] With the above configuration, the influence on the entire system can be minimized in response to the occurrence of an abnormality in the main management station 1, but it cannot be said that there are still problems.

That is, in the above configuration, the sub pipe ring station 2
In order to operate the loop network under the control of There is no transmission coupling means with 3c and 3d, and communication becomes impossible.

Furthermore, although control is entered in loopback mode as described above, until the loopback is completed, which detects the abnormality in the loop network and avoids the abnormality, the upstream stations sequentially start from the most downstream station. It requires complex procedures such as searching for abnormal stations using loopback commands and test data, sending/receiving commands based on transmission path selection, and confirmation using test data. For this reason, in today's situation where the number of node stations is increasing significantly due to the increase in terminal equipment, the time it takes to complete loopback becomes extremely long, making it difficult to use in systems that require a high degree of reliability. The problem is big.

[Object of the Invention] The present invention solves the above-mentioned drawbacks of the prior art, and when an abnormality occurs in the main management station, it is possible to quickly perform control management without forming a loopback mode as in the past. The aim is to provide a new loop network configuration method that allows the transition to control and management by sub-pipeline stations.

[Summary of the Invention 1 The gist of the present invention is that the main management station and the sub-pipe ring station are not connected in series as in the conventional example, but are connected in parallel using a turnout and switch. If an abnormality occurs, the transmission line is immediately bypassed via the sub-pipe ring station using a switch, and system control management can continue according to the previous loop transmission line without forming a loopback on the transmission line. It's a good thing.

[Example] The present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a specific configuration of a management station portion according to the present invention, and FIG. 2 is an explanatory diagram showing the configuration of a loop network according to the present invention using the management station of FIG. , each general node station 3
The configurations of a to 3d and their connections are the same as in the case of FIG. 3 already described.

The management station is the main management station 1. The main management station 1 and the sub-management station 2 are connected to the transmission line not in series as shown in Fig. 3, but as shown in Fig. 2. connected in parallel.

FIG. 1 shows the main management station 1, sub-management station 2, and the main loop 4 and slave loop 5 of the transmission line.
In the figure, 8.8- is an optical switch, and 9.9- is an optical branching device. optical splitter 9,
9' equally distributes the signals of the main loop 4 and the slave loop 5 to the main management station 1 and the sub management station 2, and the optical switches 8 and 8- can switch and connect these signals to either station. It is composed of

In the above case, when the main management station 1 is operating normally, the optical switches 8, 8- are all selected so as to be able to connect the transmission signal to the main management station 1 side. That is, the signal of the main loop 4, which is transmitted in the clockwise direction as shown by the arrow, is distributed by the optical splitter 9 into a route 41 on the main management station side and a route 41 on the sub management station side. 4 is selected as the main management station 1 side, and the optical switch 8 connected to the main management station 1 is connected to the main loop 4 via the route 42.
However, the route 4-2 on the sub-management station side is blocked. Similarly, the signal of the slave loop 5 is distributed to the routes 51 and 5-1 by the optical splitter 9'', but the optical switch 8- selects the main management station 1, and the signal is routed to the slave loop via the route 52. 5 is connected, but the route 5-2 from the sub-management station 2 is cut off.

As a result of the above, all the main and slave signals of the loop network during normal operation are circulated through the main management station 1, and the sub-management station 2 only monitors the signals distributed from the branch.

In the above case, when an abnormality occurs in the main management station 1, the optical switches 8.8-, which had previously selected the main management station 1, simultaneously select the sub-management station 2. Then, the signal of the main system loop 4 gets a transmission path from route 4-1 → sub-management station 2 → route 4-2 → main system loop 4, and the signal of the slave system loop 5 gets a transmission path from route 5-x-sub-management station A transmission path from station 2 to root 5° 2 to slave loop 5 is obtained, and the sub-management station 2 is now able to control and manage the entire loop.

As described above, according to the present invention, there is no need to complete a loopback as in the conventional example, and switching to the sub-management station 2 is achieved by a so-called instantaneous operation of switching the optical switch. The superior utility of the present invention is self-evident when comparing the amount of time required to complete the loopback in the example.

Note that even if the installation positions of the optical switch and optical splitter are replaced, there is no place to place them in terms of operation.Furthermore, although the above example shows the case where the transmission line is configured with optical fibers, the same result can be obtained even if metal communication lines are used. It is possible to form it into a configuration.

[Effects of the Invention] As described above, according to the loop network configuration method according to the present invention, the following excellent effects can be achieved.

(1) When switching from the main management station to the sub-management station, it will not go into a loopback state like in the past, and even if an abnormality occurs in other node stations or transmission lines, it will not disconnect from the loop network. There is no possibility of a node station being created.

(2) Switching to the secondary management station is achieved with the instant action of switching a switch, rather than having to enter loopback mode, making it possible to reuse the loop network in an extremely short period of time, greatly improving reliability. It can be improved.

(3) Since the signal from the main management station is cut off by the switch, there is no risk that the system will be disturbed by an abnormal signal issued from the main management station in an abnormal state.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a specific configuration of a management station according to the present invention, FIG. 2 is an explanatory diagram showing a configuration example of a loop network according to the present invention, and FIG. 3 is an explanatory diagram showing a configuration example of a conventional loop network. It is an explanatory diagram. 1: Main management station, 2: Sub pipe ring station, 3a, 3b, 3c, 3d general node stations, 4: Main loop, 5: Slave loop, 8.8-: Switch, 9+9-: Branch. Agent Patent Attorney Fujio Sato II Figure C - Self-Review Note ° Steen 3

Claims (1)

[Claims] (1) A loop network in which a management station that manages and controls the entire system and a general node station that serves as an input/output station to the network are connected in a loop through a main transmission line and a slave transmission line that runs in the opposite direction. In this case, the management station is composed of a main management station and a sub-management station, which are connected in parallel by a branch and a switch, and when an abnormality occurs in the main management station, the transmission line is sub-managed by the switch. A loop network configuration method configured to allow switching to the station side.