JPH0690282A - Faulty line recovery monitoring system - Google Patents

Abstract

PURPOSE:To provide line switching devices of low operation cost by connecting transmission and reception lines of a main circuit by one line switching device at the time of fault recovery and sending a fault recovery discriminating signal to the circuit by the other then and switching communication from a standby circuit to the main circuit after confirming reception of this signal by both of line switching devices. CONSTITUTION:When a fault of the main circuit consisting of a transmission line 24 and a reception line 25 is recovered, a line switching device (slave) 2a and a line switching device (master) 2b perform the fault recovery test of the main circuit. The control part of the line switching device 2b connects a test signal generator 21 and a signal detector 22 to the transmission line 24 and the reception line 25 respectively. The control part of the line switching device 2a sets transmission and reception lines 24 and 25 to a turning-back connection state 2e to connect the signal detector 2b. When detecting a fault recovery discriminating signal 2c from the test signal generator 21 by signal detectors 2b and 22, control parts of line switching devices 2a and 2b judge the lines 24 and 25 to be not faulty and switch the communication from the standby circuit to the main circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a failure line recovery monitoring system for monitoring a communication state of a communication line and switching to a protection line when a line failure is detected.

[0002]

2. Description of the Related Art Conventionally, in this type of system, for example, in a communication system in which a master station device and a slave station device communicate through a line switching device and a modem, when a line failure of the main line is detected, the main line is protected. Switch to and continue communication on the standby line, and check for main line failure. When the failure of the main line is recovered, a pseudo signal for testing the line, such as JIS, is sent from the modem or line switching device on the main station side.
It is determined that the line failure has been recovered by sending C 6361 and the slave station receiving it, and the communication of the protection line is switched to the main line. In another method, in the line recovery test, the line switching devices at both ends of the line report to the line management device that pseudo signals have been received from the opposing line switching devices, and the line management device sends a backup line to the line switching device. Issued a command to switch to the main line.

[0003]

However, in the method of confirming the recovery of the failure by sending a test signal to one of the main lines which has recovered the failure and the reception side receiving the signal, the other line of the transmission / reception line is Not confirmed. Therefore, there is a problem that communication is interrupted when switching is performed when the failure of the other line is not recovered.

Further, in the method of reporting the line recovery to the line management device, the recovery of both the transmission line and the reception line can be confirmed, but there are two reporting lines connecting the line management device and the master station device and slave station device report. There was a problem that it was necessary to provide it, and the equipment cost was high.

An object of the present invention is to solve the above-mentioned problems and to provide a line switching device having a low operation cost by completely detecting the recovery of a line failure and returning a backup line at an early stage.

[0006]

According to a first aspect of the present invention, one end of one or a plurality of first lines and a plurality of second lines that perform bidirectional communication and one end of the second transmission line are connected to the first transmission / reception unit.
A first line selecting means for selectively connecting the first transmitting / receiving means to the first line or the second line, a signal sending means for sending a failure recovery judgment signal, and a signal for the receiving line are provided. The first signal detecting means for detecting and the first transmitting / receiving means are connected to the second line by the first line selecting means, and the failure recovery judgment signal is sent from the signal sending means to the transmission line of the first line. And a first line switching device having a first control means for transmitting the signal to a receiving line of the first line by the first signal detecting means, and a first communication line and a second communication line. Of the receiving line and a second line selecting means connected to the other end of the second transmitting / receiving means for selectively connecting the second transmitting / receiving means to the first line or the second line. A second signal detecting means for detecting a signal; Second control for connecting the transmitting / receiving means of No. 1 to the second line, connecting the transmission line and the receiving line of the first line, and causing the second signal detecting unit to detect the signal of the receiving line of the first line. And a second line switching device having means.

[0007]

According to the present invention, the opposite line switching device switches the communication to the standby line when the main line fails. When the fault is recovered, one line switching device connects the transmission / reception line of the main line, and the other line switching device sends a fault recovery determination signal to the line. When both sides confirm the reception, communication is switched from the protection line to the main line. Therefore, unlike the prior art, the detection of the one-way failure recovery prevents the communication from being interrupted when the main line is switched and there is a failure.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fault line recovery monitoring system according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows the system configuration of the fault line recovery monitoring system of the embodiment. The line switching devices 1a and 1b are normally connected to the line switching devices 10 and 1 respectively.
1, the slave station device 1c and the master station device 1d are connected to the main line 1
Two-way communication is performed by connecting to e.

When the main line 1e fails, the line switching devices 1a and 1b switch the connection of the line switching devices 10 and 11, respectively, and the slave station device 1c is switched to the line switching device 1c.
The spare line 1f is connected to the exchange 1h through 0, and the main station device 1d is connected through the line switch 11 to the exchange 1h through the spare line 1g. Master station device 1d and slave station device 1c
Can resume bidirectional communication via the exchange 1h.

The line switching devices 1a and 1b have the above-mentioned line switching function and a failure recovery test function. In the failure recovery test, one of the line switching devices becomes the master side and sends the test signal, the other becomes the slave side, receives the test signal and returns to the main side, and both sides confirm the recovery of the failure by detecting the test signal. It is a test to do.

FIG. 1 shows a fault line recovery monitoring system of this embodiment. The line switching devices 2a and 2b connected to both ends of the main line 20 in FIG.
Although b is the master side and the line switching device 2a is the slave side, the reverse relationship can also be configured. Each of the line switching devices 2a and 2b has a test signal generator 21 that sends a failure recovery determination signal 2c in the case of the master side, and signal detectors 22 and 2f for detecting the received signal in the case of the master-slave case. On the subordinate side, the transmission line 24 and the reception line 25 of the main line 20 are turned back to the connection 2e. The master-slave side is provided with a control unit (not shown) that controls the above-mentioned test function.

When the failure of the main line 20 in FIG. 1 is recovered, the line switching device (subordinate) 2a and the line switching device (main)
2b performs a failure recovery test of the main line 20. The control unit of the line switching device (main) 2b connects the test signal generator 21 to the transmission line 24 and the signal detector 22 to the reception line 25. The control unit of the line switching device (subordinate) 2a uses the transmission / reception line 2
The signal detector 2 is provided with the loops 4 and 25 in the folded connection 2e state.
Connect f.

The fault recovery judgment signal 2c output from the test signal generator 21 to the transmission line 24 by the control unit of the line switching device (main) 2b is the return connection 2e of the line switching device (slave) 2a.
Through the receiving line 25 to the line switching device (main) 2b. Reception of the fault recovery determination signal 2c is detected by the signal detector 2f in the line switching device (subordinate) 2a and by the signal detector 22 in the line switching device (main) 2b. The control units of the line switching devices (subordinate) 2a and 2b determine that there is no fault in the transmission / reception lines 24 and 25 by detecting the fault recovery determination signal 2c.

If this is applied to FIG. 2, the line switching device 1
After determining failure recovery, a and 1b automatically connect the slave station device 1c and the call line 1f and the master station device 1d and the standby line 1g to the main line 1e by the line switching devices 10 and 11, respectively. Can be switched to.

FIG. 3 shows network management to which the failure line recovery monitoring system of this embodiment is applied. The line switching devices (slave) 3a-1 to 3a-n are the slave station devices 3c-, respectively.
1 to 3c-n and connected to the main station devices 3d-1 to 3d-n
Is connected by a collective line switching device (main) 3b connected to the main lines 3e-1 to 3e-n. In addition, the line switching devices (subordinate) 3a-1 to 3a-n and the collective type line switching device (main) 3b include the auxiliary reporting lines 3f-1 to 3f-.
n and 3g-1 to 3g-n are connected to the exchange 3h. The exchange 3h is connected to the collective type line switching device (main) 3b through the reporting line 3i, and is connected to the line management device 3k through the reporting line 3j.

The line switching devices (subordinate) 3a-1 to 3a-n and the collective line switching device (main) 3b are the main lines 3e-1.
~ 3e-n if a faulty line is detected, the line 3f-1 ~
Starting the exchange 3h from 3f-n and 3g-1 to 3g-n, connecting to the line management device 3k via the exchange 3h,
Report the occurrence of a faulty line.

The line management device 3k gives an instruction to switch the faulty line to the spare reporting lines 3f-1 to 3f-n. The line switching devices (subordinate) 3a-1 to 3a-n and the collective type line switching device (main) 3b are used as backup reporting lines 3f-1 to 3f-1.
It connects to the exchange 3h by a line designated from f-n, sets the route of the backup line via the exchange 3h, and sets the slave stations 3c-1 to 3c-n and the master station 3
The slave station device and the master station device that used the faulty line in d-1 to 3d-n are switched to the backup line.

Next, the line switching devices (subordinate) 3a-1 to 3a-n and the collective type line switching device (main) 3b connected to the faulty line are treated as shown in FIG.
When the failure recovery test is performed by the failure line recovery monitoring method of No. 3, and the failure is determined to be recovered, the collective switching device (main) 3b
Connects to the line management device 3k via the exchange 3h from the reporting line 3i and reports the failure recovery. Thereafter, the line management device 3k instructs the line switching devices (slave) 3a-1 to 3a-n and the collective line switching device (main) 3b to switch from the reporting line 3j to the recovered main line via the exchange 3h. Can be given.

In FIG. 3, a collective line switching device (main)
3b can be replaced with a plurality of line switching devices each containing one main line and one backup line. Preliminary reporting lines 3f-1 to 3f-n and 3g-1 to 3g-
A circuit-switched telephone network, a data communication network, and a packet communication network are used for n, and the effect is the same.

The line switching devices 1a and 1b of FIG. 1 and the line switching devices (slave) 3a-1 to 3a-n and the collective type line switching device (main) 3b of FIG. A failure recovery test function can be provided, or one of them can be a master function and the other can be a slave function.

The switching from the backup line to the main line after the fault recovery judgment signal is received by the line switching device can be performed manually, automatically or by remote control.

[0023]

According to the present invention, after the failure recovery of the main line,
A test signal is transmitted to the transmission / reception line to confirm failure recovery, and then the communication of the protection line is switched to the main line. For this reason,
Since there is no interruption in communication after switching as in the past,
The switching time after failure recovery is faster on average. as a result,
The use period of the backup line becomes shorter than before, and the usage fee of the backup line at the time of line failure is reduced.

The failure recovery report is reported from the main line switching device to the line management device, so that communication network management is unified, the management processing time for line switching is shortened, and the operating cost of the line management device is reduced. effective.

[Brief description of drawings]

FIG. 1 is a block diagram of a line switching device showing an embodiment of a fault line recovery monitoring system of the present invention.

FIG. 2 is a configuration diagram of a communication system of the present embodiment.

FIG. 3 is a configuration diagram of a network unified management system of the present embodiment.

[Explanation of symbols]

21 Test signal generator 22, 2f Signal detector 10, 11, 3a-1 to 3a-n Line switcher 1a, 1b Line switcher 1c, 3c-1 to 3c-n Slave station device 1d, 3d-1 to 3d- n Main station device 2c Fault recovery determination signal 3b Collective line switching device 3e-1 to 3e-n Main line 3f-1 to 3f-n, 3g-1 to 3g-n Preliminary report / line switching device 3h Switch 3k line Management device 3i, 3j Reporting line

Claims (2)

[Claims] 1. An end of one or a plurality of first and second lines for two-way communication and a first transmitting / receiving means, the first transmitting / receiving means being connected to the first line, or Second
First line selecting means for selectively connecting to the other line, signal transmitting means for transmitting a failure recovery determination signal, first signal detecting means for detecting a signal on the receiving line, and The first transmission / reception means to the second
A signal for determining a failure recovery from the signal transmission means to the transmission line of the first line, and the first signal detection means to detect the signal of the reception line of the first line. And a second transmission / reception unit, the second transmission / reception unit is connected to the first line switching device, the other ends of the first communication line and the second communication line, and the second transmission / reception unit. Second line selecting means for selectively connecting to the second line or the second line, second signal detecting means for detecting the signal of the receiving line, and second line selecting means Second transmitting and receiving means
Second control means for connecting the transmission line and the reception line of the first line and detecting the signal of the reception line of the first line by the second signal detection means. 2. A fault line recovery and monitoring system comprising a line switching device of 2. 2. The first line switching device, wherein after the failure recovery determination signal is sent to the transmission line of the first line and the signal is detected on the reception line, the first control means The first line selecting unit changes the connection of the first transmitting / receiving unit from the second line to the first line, and in the first line switching device, after detecting a signal on the receiving line,
2. The fault line recovery monitoring system according to claim 1, wherein the second control unit changes the connection of the second transmission / reception unit from the second line to the first line by the second line selection unit. .