Method of generating 3R section information

摘要

An economical optical network is constituted by effectively using network resources by using the minimum number of, or minimum capacity of 3R repeaters. An optical node device being a source node transmits an optical test signal each time an optical path is set for optical node devices contained in a route to a destination node one hop at a time in order from a next hop adjacent optical node device of the optical node device being the source node. Each time the optical test signal is transmitted, the optical node device being the source node receives a report of deterioration in the state of the optical test signal from an optical node device at the farthest end that receives the optical test signal. When the deterioration in the state of the optical test signal based on the received report satisfies a predetermined deterioration condition, the optical node device being the source node gives notification to an optical node device one hop before the optical node device at the farthest end that the optical node device one hop before the optical node device at the farthest end is a 3R destination node, and also a 3R source node of a next 3R section. An optical node device which receives the notification operates in the same manner as the source node being the source node.