WDM NETWORK AND WDM NETWORK DEVICE

摘要

PROBLEM TO BE SOLVED: To lighten the load of switching processes at both ends of a light-wave path when a wavelength multiplex network recovers from a fault in light-wave path units and to enable adaptation to an increase in scale by multi-ring constitution. SOLUTION: The WDM network 401 is constituted by connecting ring networks 402 to 404 which are capable of light-wave path switching in a single ring and a light-wave path 431 is set thereupon. The ring networks 402 to 404 are set as subnetworks and the light-wave path 431 is divided into three partial light-wave paths in subnetwork units. Further, a partial light-wave path monitor and control area is provided in the overhead of the light-wave path 431, fault control information in partial light-wave path units is put therein, and faults of partial light-wave paths are detected by the subnetworks. Then switching control is performed by applying a function for switching in light-wave path unit to the partial light-wave paths and the partial light-wave path in a subnetwork 403 is switched to a standby partial light-wave path 432.