JPS6242627A - Annular transmission equipment - Google Patents

Abstract

PURPOSE:To secure the reliability of a loop network by monitoring centralizedly troubles of subordinate stations or transmission lines by a control station on the loop network and disconnecting trouble positions to reconstitute annular transmission lines if troubles occur. CONSTITUTION:If a control station 8 detects a trouble of subordinate stations 11-15 or transmission lines, one of dual annular transmission lines 9 and 10 is used to transmit a turn-back instructing signal to stations in the order from the subordinate station which is most distant in the signal transmission direction. When the turn-back indicating signal is turned back to the control station 8, this turn-back state is held. The other annular transmission line is used to perform the same processing, and these two transmission lines in the turn-back state are connected by the control station to reconstitute annular transmission lines.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a loop network having duplicated circular transmission lines for transmitting signals in opposite directions.

Conventional technology Conventionally, when a transmission path or static failure occurs in a loop network, a DC signal is superimposed and the station detects that the DC signal is disconnected and automatically turns back the transmission path. When the means for reconfiguring the annular transmission path or the station that has detected the DC signal disconnection condition is sequentially repeated as a DC signal disconnection condition for the next station I/, and this condition is detected at the control station, Measures have been used to reconfigure a circular transmission line using a transmission line specially prepared for failure monitoring.

Problems to be Solved by the Invention However, with the above-mentioned conventional ring transmission line reconfiguration means, there is a problem in that a DC signal detection circuit must be provided at each stage, and a fault monitoring and control transmission line must be provided. There was a point.

The present invention is intended to solve such problems, and aims to realize the reconfiguration of a circular transmission line using a simple algorithm and circuit.

Means for Solving the Problems In order to achieve the above object, the present invention centrally monitors faults in dependent stations or transmission lines at a control station on a loop network, and when a fault occurs, it uses a simple algorithm to detect faults in subordinate stations or transmission lines. This system detects dependent stations or transmission lines, disconnects them from the loop network, and reconfigures the circular transmission line.

Operation The present invention has the following effects due to the above-described configuration. In other words, when the control station detects a failure in a dependent station or transmission path, it sends a loopback instruction signal to the nearest station in order from the farthest dependent station in the signal transmission direction using one of the duplicated circular transmission paths. After confirming that the return instruction signal has been sent back to the control station, this return state is maintained. Furthermore, by performing similar processing on the other circular transmission line and connecting these two folded transmission lines at the control station, the circular transmission line can be reconfigured. ``Example'' An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an embodiment of the present invention. Figure 1 shows the overall configuration of the loose network8.
is a control station, 9.10 is a transmission line through which bit-serial signals flow, 11' to 15 are dependent stations, and 18.17 is a fault location. In the following embodiments, among the duplexed transmission lines, the one in operation is referred to as the λ system, and the one in hot standby is referred to as the B system, and it is assumed that a transmission failure has occurred in both the human system and the B system.

Reference numerals 1 and 4 are electrical-to-optical conversion modules for the human and animal 7B system, 3 and 6 are shift registers for the large system and B system, respectively, and 7 is a loop interface circuit for controlling frame synchronization.

Next, the operation of the above embodiment will be explained.

If a failure occurs in the above embodiment, the control station 8 detects the failure due to frame synchronization, for example. At this time, as shown in FIG. 2, the control station 8 connects circuits 2 and 6 and circuits 5 and 8, and sequentially sends a return instruction signal to each station from the farthest station 16 of the A-system transmission line. do.

When a return instruction signal is sent to the station 12, one closed circular transmission path is formed as shown in FIG. 2, and the return instruction signal is sent back to the control station 8. As a result, frames can be transmitted normally through this circular transmission path.

Next, the control station 8 uses the B-system transmission line to
Return signals are sequentially transmitted from the next closest station 13. When a return signal is sent to the station 14, one closed circular transmission path is formed as shown in FIG. 3, and a return instruction signal is sent back to the control station 8.

This allows frames to be transmitted normally through this circular transmission path.

The control station 8 can connect the circuits 4 and 6 as shown in FIG. 4 in order to combine these two annular transmission lines, forming one closed annular transmission line as a whole;
Thereafter, communication can be performed using the transmission path A system.

If communication is to be performed using the transmission line B system, circuits 1 and 2 may be connected.

Further, FIG. 5 shows an example when a failure occurs in the transmission line or station adjacent to the control station 8.

When a circular transmission line using a human transmission line is formed by the method described above, the loop transmission line is not formed even if the return instruction signal is sent out sequentially from 13 through the B system transmission line and reaches the subordinate station 15. , the control station 8 operates a loop network using only the circular transmission line of the A-system transmission line.

In this way, according to the above embodiment, the control station 8 centrally monitors the operating state of the loop network, and in the event of a failure or disconnection of the transmission line or dependent station, the reconfiguration of the loop transmission line is performed using a simple algorithm and circuit. It has the advantage that it can be done. Furthermore, the above embodiment has the effect that the reliability of the loop network can be easily ensured.

Effects of the Invention The present invention (as is clear from the above embodiments), even if a failure occurs in a subordinate stage or a part of the transmission line in a loop network, the subordinate stage 5 can be disconnected and the loop transmission line can be maintained. Since reconfiguration can be performed, it is possible to perform control to ensure the reliability of the loop network.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the overall configuration of a loop network according to an embodiment of the present invention; FIG. The figure shows the configuration of a reconstructed 7'fvO ring transmission line, and FIG. 5 is a block diagram of the ring transmission line when a failure occurs in the transmission line (B system) adjacent to the control station. 8-...Control station, 11-16...Subordinate station, 16, 1 completed...Fault location. Name of agent: Patent attorney Toshio Nakao and one other person δ−
-＠J Gostain 2nd 11-15-11th Bisei University Ten, N/6~/7- Obstacles-V Tsutsujo Figure 1 Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) A loop network that connects in series a duplexed ring transmission line in which signals are transmitted in opposite directions, a control station that has a supervisory control function for the ring transmission line, and multiple subordinate stations that do not have a supervisory control function. When a part of the transmission path or a subordinate station connected to the loop network is separated from the loop network and the circular transmission path is reconfigured, the control station uses one of the duplicated circular transmission paths to A transmission line return instruction signal is sent from the farthest subordinate station to the nearest subordinate stations in the transmission direction, and after confirming that the return instruction signal has been sent back to the control station, this return state is maintained. , and using the other annular transmission path in the direction of signal transmission,
The next closest station to the dependent station that has already maintained the loopback state sends a transmission line loopback instruction signal in the same way as before, and after confirming that the loopback instruction signal has been sent back to the control station, this loopback operation is started. A ring transmission device characterized in that a ring transmission line is constructed again by maintaining the transmission line in the two folded states and coupling the transmission lines in the two folded back states at a control station. (2) When a transmission line adjacent to a control station or a dependent station is disconnected, a ring-shaped transmission line is formed while remaining in one folded state formed by a fold-back instruction signal. The ring transmission device described.