JPH04134942A - Communication line switching system at fault state of modem - Google Patents

Abstract

PURPOSE:To improve the reliability of a data during backup by using selectively an INS net 64 for backing up a communication line when a private line of a MODEM is faulty. CONSTITUTION:When a fault takes place in a private line 5, a control section 18 controls a terminal adaptor section 12 to use a 2nd B-channel of an INS net 64 line 6 for the connection with a terminal adaptor section 13 of a MODEM 2. Control sections 18, 19 of MODEMs 1, 2 control switches 16, 17 to change over a path for data terminal equipments 3, 4 and MODEM sections 10, 11 into a path for terminal adaptor sections 12, 13, and the connection through the private line 5 between the MODEMs 1, 2 is backed up through a 2nd B- channel of INS net 64 lines 6, 7. Thus, since one line of the INS net 64 is used in parallel for a backup line for the private line and a line for sending diagnostic information, disable transmission of diagnostic information during backup is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a communication line switching system when a modulation/demodulation device fails.

[Prior Art] Conventionally, public lines have been mainly used as a backup line for communication lines in the event of a failure of a dedicated line for a modem and as a transmission of diagnostic information.

[Problems to be Solved by the Invention] As mentioned above, in order to back up the communication line and transmit diagnostic information in the event of a fault in the dedicated line, two public lines (4-wire system) and diagnostic information are required for backing up the dedicated line. A total of three lines, one public line (two-wire type), were prepared for transmission, and there were problems with the per-line usage fee, H/W volume (equipment cost), etc.

Although it is possible to use the public line for backup purposes also for transmitting diagnostic information, in this case there is a problem that diagnostic information cannot be transmitted during backup.

The present invention solves the above-mentioned problems of the conventional system, but does not use a public line as a backup for the dedicated line.

[Means for Solving the Problems] According to the present invention, the INS net 64 is switched and used for backing up the communication line in the event of a dedicated line failure of the modem. A method for switching communication lines when a modem failure occurs can be obtained.

Further, according to the present invention, the INS net 64 is switched and used for backing up the communication line in the event of a dedicated line failure of the modem, and the first B channel of the two B channels of the INS net 64 is used to back up the dedicated line. The present invention is characterized in that the diagnostic information is transmitted through the second B channel. Further, according to the present invention, there is provided a device that switches and uses the INS net 64 for backing up a communication line when a dedicated line of a modem is faulty, wherein line, DT
A diagnostic unit that diagnoses the E interface and the modulation/demodulation device itself, and a diagnostic unit that connects to the opposing modulation/demodulation device via the INS net 64 as a backup line when a dedicated line failure occurs, and the diagnostic information obtained by the diagnostic unit is connected to the INS network. 64 provides a modulation/demodulation device with a two-communication line switching function, which has a terminal adapter section for transmitting data to a remote location, and a control section for controlling the diagnostic section and the terminal adapter section.

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

In a configuration in which the modem 1 is connected to the modem 2 via a dedicated line 5, the modems 1 and 2 include a line, a DTE interface la between them and the data terminal device 3.4,
2a, and a diagnostic unit 1 that diagnoses the state of the modem 12.
4.15, when a failure occurs in the dedicated line 5, the INS net 64 network shown as 8 is used as a backup line to connect to the modem 2, and the information obtained by the diagnostic section 18.19 is transmitted remotely via the INS net 64. Terminal and adapter part 1 for transmitting data to the local network monitoring center 9
2.13, data terminal equipment 3.4 and modem unit 10.1
1 and a terminal adapter part 12.13, and a control part 18.19 to control them.

Note that in the above configuration, the data end modulation/demodulation device 1゜2 is
The diagnostic section 14.15 diagnoses the dedicated line 5 (INS net 64 line during line backup), the DTE interface, and the modem itself, and periodically or when an alarm occurs, the control section 18.19 activates the terminal adapter section 12.13. Control INSNS net 64 line 7 2
IN using the first B channel of the two B channels.
S net 64 connects to network monitoring center 9 via network 8 and transmits diagnostic information.

The modem devices 1 and 2 perform the operations described above, and at the same time, if a failure occurs in the dedicated line 5, the control section 18 controls the terminal adapter section 12 to connect to the INSNS network 64.
It is connected to the terminal adapter unit 13 of the modem 2 using the second B channel of the line. The control section 18.19 of the modem 1.2 controls the switch 16.17 to switch the path between the data terminal device 3.4 and the modem 10.11 to the path with the terminal adapter section 12.13, and the modem 1.Connection via dedicated line 5 between 2 to INSNS Net 6
A second B channel of 4 lines 7 can be used as a backup.

[Effects of the Invention] As explained above, according to the modem with communication line switching function of the present invention, by using one line of the INS net 64, it can be used in parallel with the backup line of the dedicated line and for transmitting diagnostic information. Since it can be used easily, it has an effect on the usage fee for one line and the H/W volume (equipment cost). Furthermore, since the quality of the INS net 64 is better than that of public lines, it also improves the reliability of data being backed up.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention. Explanation of symbols = 1, 2...modulator/demodulator, la, 2a...
・DTE data interface, 3, 4... Data terminal device, 5... Dedicated line, 6, 7... INS Net 64 line, 8... INS Net 64 network, 9... Network monitoring center, 10 .11...modulation/demodulation section, 12
．． 13...Terminal adapter section, 14.15...Diagnosis section, 16.16a, 17, 17a...Switch. 18.19...Control unit.

Claims (3)

[Claims] (1) A communication line switching method in the event of a failure of the modem, characterized in that the INS net 64 is switched and used for backing up the communication line in the event of a failure of the dedicated line of the modem. (2) Switching and using the INS net 64 as a backup communication line in the event of a failure of the dedicated line of the modem, and
When a modulation/demodulation device fails, the first B channel of the two B channels of NS Net 64 is used to back up the dedicated line, and the second B channel is used to transmit diagnostic information. Communication line switching method. (3) A device that switches and uses the INS net 64 for backing up the communication line in the event of a failure of the dedicated line of the modem, including a diagnostic unit in the modem that diagnoses the line, DTE interface, and the modem itself, and a dedicated INS as a backup line in case of line failure
a terminal adapter section for connecting to the opposing modem device via the net 64 and for transmitting diagnostic information obtained by the diagnosis section to a remote location via the INS net 64; and a control section for controlling the diagnosis section and the terminal adapter section. A modem device with a communication line switching function.