Patent ID: 8244123
Filing Date: 2012-08-14
Classification: H04B

Abstract:
1. An optical transmission system comprising: a first monitoring section configured to monitor a first optical signal on a first optical transmission line to detect a first failure; a modulating section configured to generate a second optical signal obtained through modulation of a signal corresponding to the first optical signal based on the first failure, to transmit the second optical signal onto a second optical transmission line which is connected with said first optical transmission line and a terminal unit; a second monitoring section configured to monitor the second optical signal on said second optical transmission line to detect a second failure; a detecting section configured to detect the first failure from the second optical signal on said second optical transmission line; and a line switch configured to selectively switch an optical transmission line to be connected with said terminal unit, from said second optical transmission line to another optical transmission line based on the first failure detected by said detecting section and the second failure detected by said second monitoring section.