JPH05110547A - Automatic circuit switching unit - Google Patents

Abstract

PURPOSE:To facilitate a maintenance and an inspection by recording history of circuit switching by providing a memory means in which switching history is recorded, whenever switching is executed, in a CPU part. CONSTITUTION:In a CPU part 40, a memory part 43 in which switching history is recorded, whenever switching is executed is provided. In such a state, by monitor parts 20-2n inserted between data terminal equipments 1-(n) and data terminating equipments 30-3n, a data communication signal is always monitored. When the monitor parts 20-2n detect deterioration of a receiving signal, the CPU part 40 decides that the existing circuit is abnormal, and switches automatically the circuit to a backup circuit. Also, at the time point when switching is completed, this history is recorded in the memory part 43, and when a state of the existing circuit is recovered, the backup circuit is switched automatically to the existing circuit again. In such a way, it becomes possible to record the switching history in advance and to read it out afterward, and a maintenance and an inspection are facilitated.

Description

Detailed Description of the Invention

[0001]

The present invention is used in data communication networks. In particular, it relates to a backup line switching technology when a leased line fails.

[0002]

2. Description of the Related Art In a data communication network for transmitting and receiving data by connecting a signal from a data terminal device to a working line through a data terminating device, when a failure occurs in this working line, the line is automatically switched to the ISDN line. It is configured to switch and connect to a public line for backup. The occurrence of a failure is detected by the monitor unit inserted between the data terminal device and the data terminating device monitoring the signal state.
When the monitor detects the deterioration of the signal quality, the changeover switch is activated, and the signal is automatically transmitted / received through the public line of ISDN. After that, if the monitor detects that the working line has been restored, the line is automatically switched again from the ISDN public line to the working line.

[0003]

This line switching and restoration are all performed automatically, which is convenient, but when the working line continues to fail for a long time and requires manual maintenance or periodic inspection, There is a problem that the history of line switching so far is not recorded, and it becomes impossible to obtain a clue in searching for a failure point.

The present invention has been made against such a background, and an object thereof is to provide an automatic line switching device for recording a line switching history and facilitating maintenance and inspection.

[0005]

SUMMARY OF THE INVENTION The present invention is a data terminal device for performing data communication, a data terminal device connected to the data terminal device for terminating data, and inserted between the data terminal device and the data terminal device. An automatic line switching device including a monitor unit that monitors the state of a signal, a CPU unit that controls line switching based on information from this monitor unit, and a changeover switch that is controlled by this CPU unit and that switches and connects lines. In the above, the CPU unit is provided with a memory means for recording a switching history each time switching is performed.

Further, it is desirable that the contents of the switching history recorded in the memory means include the ID number of the factor causing the switching, the switching direction, the switching time, and the port to be switched.

[0007]

The data communication signal is constantly monitored by the monitor unit inserted between the data terminal device and the data terminating device.
When the monitor detects the deterioration of the received signal, the CPU determines that the working line is abnormal, and automatically switches the line to the backup line. Here, the ISDN public line is used as a backup line. When the switching is completed, this history is recorded in the memory unit. When the state of the working line is recovered, the backup line is automatically switched back to the working line.

The recorded contents are the ID number of the cause of the switching, the switching direction, the switching time, and the port to be switched, and are read out to the display during maintenance and inspection to assist in the search for the faulty part.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the device of the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention.

The present invention relates to data terminal devices 1 to n for performing data communication, data terminating devices 30 to 3n connected to the data terminal devices 1 to n for terminating data, and the data terminating devices 30 to 3n and data terminals. Monitor units 20 to 2n inserted between the devices 1 to n for monitoring the state of signals, a CPU unit 40 for controlling line switching based on information from the monitor units 20 to 2n, and controlled by the CPU unit 40. In the automatic line switching device including the changeover switches 10 to 1n for switching and connecting lines, the CPU unit 40 is provided with a memory unit 43 in which a switching history is recorded every time switching is performed.

The contents of the switching history recorded in the memory unit 43 include the ID number of the factor causing the switching, the switching direction,
The switching time and the port to be switched.

Next, the operation of the apparatus of the present invention will be described with reference to FIG. FIG. 2 is a flow chart showing the operation of the apparatus of the present invention.

The normal changeover switches 10 to 1n are connected to the working line side, and the data terminal devices 1 to n are connected to the data terminating devices 30 to 3n, respectively. The monitor units 20 to 2n constantly monitor the states of the control signals of the data terminating devices 30 to 3n, and the CPU unit 40 periodically captures them.

The data terminating device 30 ...
When the received signal quality of 3n is deteriorated and the monitor units 20 to 2n detect it and the CPU unit 40 recognizes it, the CPU unit 40
Switch 1
0 to 1n are automatically switched to the backup line side, the signals of the data terminal devices 1 to n are connected to the multiplexing unit 44, and connected to the ISDN line 46 via the terminal adapter unit 45.

Also, during backup, the CPU section 40 monitors the line that caused the switching, and if it determines that the line has been restored to its original state, it automatically switches the changeover switches 10 to 1n to the working line side.

The CPU section 40 writes the ID of the factor causing the switching, the switching direction, the switching time, and the port to be switched in the memory section 43.

When performing maintenance inspection, the contents of the switching history can be confirmed on the display unit 41 by operating the key operation unit 42.

In the present embodiment, the contents of the memory are set to the ID of the factor causing the switching, the switching direction, the switching time, and the port to be switched. However, in addition to this, data for assisting maintenance and inspection may be stored. Can also

[0019]

In the data communication network, the contents of the switching history are recorded in the memory unit and are output by key operation and displayed, so that the trouble location can be easily found by the past switching history at the time of maintenance and inspection.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the apparatus according to the present invention.

[Explanation of symbols]

 1-n data terminal device 10-1n changeover switch 20-2n monitor unit 30-3n data termination device 40 CPU unit 41 display unit 42 key operation unit 43 memory unit 44 multiplexing unit 45 terminal adapter unit 46 ISDN line

Claims (2)

[Claims] 1. A data terminal device for performing data communication, a data terminal device connected to the data terminal device for terminating data, and a signal state inserted between the data terminal device and the data terminal device to monitor the state of a signal. An automatic line switching device comprising a monitor unit, a CPU unit for controlling line switching based on information from the monitor unit, and a changeover switch for switching and connecting lines controlled by the CPU unit. An automatic line switching device comprising a memory means for recording a switching history each time the switching is performed. 2. The automatic line switching device according to claim 1, wherein the contents of the switching history recorded in the memory means include an ID number of a factor causing switching, a switching direction, a switching time, and a port to be switched.