Patent ID: 7418203
Filing Date: 2008-08-26
Classification: H04B,H04J

Abstract:
1. A diagnosis method for standby systems, in an optical ring network comprising a plurality of optical transmission apparatuses each having a redundant configuration including an active system unit and a standby system unit, in which a plurality of optical transmission lines through which an active system optical channel and a standby system optical channel can be propagated, is used to connect adjacent optical transmission apparatuses, of said plurality of optical transmission apparatuses, to each other, to form a ring-shaped optical communication network, for diagnosing whether or not data transmission using said standby system optical channel can be performed normally, during data transmission between said respective optical transmission apparatuses using said active system optical channel, the method comprising giving a command for starting the standby system diagnosis to any one of said plurality of optical transmission apparatuses; generating by said optical transmission apparatus having received said command a false signal different from a data signal under operation in its own apparatus, providing said false signal to the standby system unit in its own apparatus, detecting based on a transmission state of said false signal whether or not said standby system unit is operating normally, and transmitting information indicating the detection result to the optical transmission apparatus on the downstream side, by utilizing a predetermined region in the active system optical channel under operation; generating by said optical transmission apparatus on the downstream side a false signal different from a data signal under operation in its own apparatus, after confirming that the standby system unit in the optical transmission apparatus on the upstream side is operating normally, according to data in the predetermined region in said active system optical channel, providing the false signal to the standby system unit in its own apparatus, detecting based on the transmission state of the false signal whether or not said standby system unit is operating normally, updating the data in the predetermined region in said active system optical channel under operation corresponding to the detection result, and transmitting the data to the optical transmission apparatus on the further downstream side; and confirming by said optical transmission apparatus having received said command normal operations of the standby system units in all optical transmission apparatuses on the ring network, according to the data in the predetermined region in the active system optical channel, which has made a round of the ring network, and outputting information indicating the finish of the standby system diagnosis.