JPS5742248A - Switching device for communication system - Google Patents
Switching device for communication systemInfo
- Publication number
- JPS5742248A JPS5742248A JP55118167A JP11816780A JPS5742248A JP S5742248 A JPS5742248 A JP S5742248A JP 55118167 A JP55118167 A JP 55118167A JP 11816780 A JP11816780 A JP 11816780A JP S5742248 A JPS5742248 A JP S5742248A
- Authority
- JP
- Japan
- Prior art keywords
- communication system
- modem12b1
- data terminal
- carrier detection
- modem12b2
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Maintenance And Management Of Digital Transmission (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
Abstract
PURPOSE:To make automatic switching of a communication system efficiently at failures with a simple constitution, by using a carrier detection function, in a data communication system having a duplex system. CONSTITUTION:When a communication line 13a from an MODEM12a1 to an MODEM12a2 is cut off, a carrier detection signal outputted from the MODEM12a2 is turned off, and a changeover device 142 changes over the connection consisting of a data terminal device 112 and the MODEM12b2. Carriers are transmitted from the MODEM12b2, it is detected with the MODEM12b1 and the carrier detection signal outputted from the MODEM12b1 is turned on and a changeover device 141 changes over the connection consisting of a data terminal 111 and the MODEM12b1. As a result, the data terminal devices 111, 112 are automatically connected from the communication system A to the system B.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP55118167A JPS5742248A (en) | 1980-08-27 | 1980-08-27 | Switching device for communication system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP55118167A JPS5742248A (en) | 1980-08-27 | 1980-08-27 | Switching device for communication system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5742248A true JPS5742248A (en) | 1982-03-09 |
Family
ID=14729765
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP55118167A Pending JPS5742248A (en) | 1980-08-27 | 1980-08-27 | Switching device for communication system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5742248A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60163551A (en) * | 1984-02-03 | 1985-08-26 | Nec Corp | Line switching system |
JPS6148249A (en) * | 1984-08-13 | 1986-03-08 | Nec Corp | Line switching device |
JPS61208330A (en) * | 1985-03-13 | 1986-09-16 | Mitsubishi Electric Corp | Controller for redundant communication line |
JPS61269442A (en) * | 1985-05-23 | 1986-11-28 | Tokyo Electric Co Ltd | Switching device for data transmission loop |
JPS6258746A (en) * | 1985-09-06 | 1987-03-14 | Nippon Telegr & Teleph Corp <Ntt> | Circuit backup system |
-
1980
- 1980-08-27 JP JP55118167A patent/JPS5742248A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60163551A (en) * | 1984-02-03 | 1985-08-26 | Nec Corp | Line switching system |
JPS6148249A (en) * | 1984-08-13 | 1986-03-08 | Nec Corp | Line switching device |
JPH0438172B2 (en) * | 1984-08-13 | 1992-06-23 | Nippon Electric Co | |
JPS61208330A (en) * | 1985-03-13 | 1986-09-16 | Mitsubishi Electric Corp | Controller for redundant communication line |
JPS61269442A (en) * | 1985-05-23 | 1986-11-28 | Tokyo Electric Co Ltd | Switching device for data transmission loop |
JPS6258746A (en) * | 1985-09-06 | 1987-03-14 | Nippon Telegr & Teleph Corp <Ntt> | Circuit backup system |
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