JPH02181546A - Token ring lan branch separation and control system - 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] [Field of Industrial Application] The present invention relates to a spur fault countermeasure method for a token ring LAN consisting of a plurality of DUs (configuration control units) and a closed ring transmission line, and the present invention relates to a spur fault countermeasure method for identifying fault spurs and The present invention relates to a branch line separation method suitable for separating spurs.

[Conventional technology]

In the conventional method, as described in Japanese Patent Application Laid-open No. 61-236247, when a fault occurs in a spur pulled out from a DU and the DU detects the spur fault, a ring is formed inside the DU and the spur joins the DU. At the same time, separate the spars that are attached. After that, a spar was added to the ring, and if there was a problem with the spar, the spar was separated. For this reason.

The spar immediately downstream of the faulty spar also appeared to be faulty, and there was a problem in that the spar immediately downstream of the faulty spar was also separated.

[Problem to be solved by the invention]

The token ring LAN failure spar disconnection method disclosed in Japanese Patent Application Laid-Open No. 61-236247 disconnects all spurs at the same time when a failure occurs. BCN: Beacon) After all spurs are separated, the transmitting station receives the BCN sent by the spurs to form a ring, becomes an active monitor, and purges (frames indicating establishment of active monitor PR)
G: Purge) is not taken into account. This causes the following problem.

When a spar that connects a station that is transmitting PRG is joined to the ring for reconfiguration, the BCN cannot orbit because it is transmitting PRG, and the DU determines that it is a faulty spar and disconnects the spar from the ring within the DU. Put it away. For this reason, when a spar failure occurs, there is a problem in that the spar downstream of the failed spar is also separated.

An object of the present invention is to provide a spar disconnection control method for reliably disconnecting a faulty spar when a spar failure occurs.

[Means to solve the problem]

In order to achieve the above objective, in the spar disconnection process, by disconnecting the spurs one by one from upstream, the stations connected to the normal spurs other than the faulty spurs receive the BCN and reset the timer TNT of each station. DU only until TNT times out
It ensures that all stations connected to a spar are standby monitors, adds spurs one by one to identify faulty spurs, and as soon as a faulty spar is found, bypasses the faulty spar and disconnects the faulty spar. .

[Effect]

By disconnecting the spurs one by one from upstream, the BCN will reach the stations connected to the spurs other than the faulty spur, and the TNT of each station will be reset.
Until the NT times out, each station is in the state of repeating the received frame, and if you add spurs one by one to identify the faulty spar, frames will disappear only when the faulty spar is added, so it is difficult to identify the faulty spar. It is possible to identify and separate only the fault spurs.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail.

FIG. 1 is a schematic diagram of a communication system implementing the present invention. In FIG. 1, 1 is an active ring, 2 is a standby ring, 3-1. ..., 3-3 is DU, 4-1. ...,
4-7 is a spar 5-1. ..., 5-7 is a station (hereinafter referred to as ST).

FIG. 2 is a schematic diagram of the internal configuration of the DU. D shown in Figure 1
Among U, DtJ3-2 is shown as an example. 6-1.6-2
is a ring control circuit that connects the active ring and standby ring and performs ring loopback.

7-1. . . , 7-3 is a spur control circuit that adds and disconnects spurs. 8 is a management ST that controls DU3-2.

FIG. 3 shows the state of the ring control circuit 6, where (, z) is O
In the normal state of N, (b) is the OFF ring return state.

FIG. 4 shows the state of the spur control circuit 7, where (α) is ON
(b) is the OFF spar disconnected state.

Part 5 is D to take countermeasures against failure spur separation according to the present invention.
3 is a flowchart of processing showing the operation of U. FIG. 6 shows an example of a sequence of operations of a DU that takes measures against failure spur isolation according to the present invention.

If the dog has a fault, the spur control circuit 7 is connected to the spur 4-4.
-2 to 5T5-4 occurs in a spur, 5T5-
4 sends the BCN and manages S that a failure has occurred in the spar.
Notify T8. Management ST8 receives the BCN and sends the second
Turn off the ring control circuit 6-1, 6-2 shown in the figure,
An inner ring is formed with DU3-2 (200). At this time, another ring is formed by DU3-1 and DU3-3. When the internal ring of DU3-2 is completed, management Sr1
begins sending out the BCN (210).

When 5T5-3 receives the BCN, it resets TNT. In 5T5-4 and 5T5-5, the BCN does not flow because the spur 4-4 has failed. Management ST8 is Spar 4
-3 is separated (100°220). Next spar 4-3
Because of the separation, BCN enters Spar 4-4 without going through 5T5-3 (230), but Spar 4
-4 is in trouble, so the BCN cannot reach 5T5-4. Management ST8 separates Spar 4-4 (100
, 240). Since spar 4-3 and spar 4-4 are separated, 5T5-5 receives BCN and TN
Reset T (250).

Management ST8 separates spar 4-5 (110°260
). Next, in order to identify and isolate the faulty spar, the spar 4-
3 joins the ring (120°270). spar 4
Since no failure has occurred in -3 (130), the management ST
The BCN sent by Spur 4-3 goes around the ring (280), and the management ST8 knows that there is no failure in Spar 4-3. When the super 4-4 joins (120, 290), the BCN sent by the management ST8 is deleted because a failure has occurred (300). Since the BCN has not made one cycle, the management ST 8 considers that the spar 4-4 is at fault and disconnects the spar 4-4 (130) (140° 310). Spur 4-5
(120°320) Since the faulty spar 4-4 is disconnected, BCN becomes one round L (330),
Management ST8 considers Spur 4-5 to be free of failure (13
0). Now that all spurs have joined (15
0°340), the management ST8 is the ring control circuit 6-1°6
Change -2 to ○N, make one ring, and finish the spur failure countermeasures.

[Effects of the Invention] The present invention achieves the following effects by implementing the method described above. When a spar fault occurs, the faulty spar can be accurately isolated by separating the spar one by one.

[Brief explanation of the drawing]

Fig. 1 is a ring configuration diagram of an embodiment of the present invention, Fig. 2 is an internal configuration diagram of DTJ3-2 in Fig. 1, Fig. 3 is a ring control circuit, Fig. 4 is a spur control circuit, and Fig. 5 is a flowchart of DU according to the present invention, and FIG. 6 is a sequence diagram of an embodiment. 1... Active ring, 2... Standby ring. 3... Configuration control device, 4... Spur 5... Station, 6... Ring control circuit, 7... Spar control circuit, 8... Management station. Suji I Etsuman 2 Audience Ward 5 Hi

Claims (1)

[Claims] 1. In the active system and standby system closed ring transmission lines, configuration control devices that change the configuration of the ring transmission path are connected in a ring shape, and the active system closed ring transmission line pulled out from the configuration control device (hereinafter referred to as DU) The D
The U has a control circuit for joining and leaving a plurality of spurs from the active ring, and when the DU detects that a failure has occurred in the spurs, the active transmission line and the standby transmission line are connected to each other within the DU. The system transmission lines form an internal ring, which is disconnected one by one from the most upstream spar inside the DU, and a beacon is sent into the branch line to reset the monitoring timer of the ST, and all spar The token ring L is characterized in that after the spar is separated, spurs are added to the inner ring one by one, and when a fault is detected in the spar, the spar is separated as a faulty spar.
AN branch line disconnection control system.