Line switching system in on-line system

Abstract

Abstract PURPOSE:To automatically switch lines, by switching a station detecting the generation of failure of an existing line or an MODEM to a spare line and transmitting a line switching instruction to a remote station through the use of a spare line. CONSTITUTION:When a line switching device of the 1st station detects a failure of an existing line through the output of an MODEM, a code transmission control circuit 88 switches a relay 89 to a contact M position through the output of a failure detection circuit 86, and a latch circuit 81 switches a switching circuit 80 to a contact M position for the changeover to a spare line 2. A line switching instruction code from a selection circuit 93 is transmitted to the switching device of the 2nd station via the MODEM, the spare line and other MODEMs. In this switching device, a switching code detection circuit 85 monitors a reception data RD from the said other MODEMs, and when the switching instruction code is detected, the latch circuit 81 changes over the relay switch of the circuit 80 to the contact M to switch the 2nd station to the spare line. The restoration to the existing line is similarly performed by transmitting a line restoration instruction code.

Inventors

• 👤 Tsunetaro Sakai
• 👤 酒井　恒太郎

Bibliographic Details