FAULT RECOVERY METHOD AND NODE FOR OPTICAL WAVELENGTH MULTIPLEXING COMMUNICATION NETWORK

摘要

PROBLEM TO BE SOLVED: To provide a fault recovery method which can be applied to an optical wavelength multiplexing communication network where plural kinds of optical paths using different wavelengths are formed and which consists of node groups in the WP mode and/or the VWP mode and links connecting them. SOLUTION: A fault recovery message broadcast from a sender node to a chooser node through each link includes at least a first table 11 where the classification of the wavelength which a disconnected optical path has been using and the number of wavelength requests for each wavelength are recorded, a second table 12 where the destination of a node is recorded, and a third table 13 where the number of available wavelengths which can be used above the node receiving the fault recovery message is recorded. Each node compares the number of available wavelengths in links on the downstream side with that in the third table and rewrites the number of available wavelengths to the smaller one of them to send the fault recovery message to the downstream side.