Patent ID: 7515829

Claim:
A wavelength division multiplexing optical transmission system in which a plurality of optical signals of different wavelengths is multiplexed in a wavelength multiplexing station to generate wavelength division multiplexed light, and the wavelength division multiplexed light is repeatedly transmitted via a plurality of stations arranged on an optical transmission line, and at least one of the plurality of stations on said optical transmission line is a path changing station which changes the path of the optical signals of the respective wavelengths included in said wavelength division multiplexed light, and said wavelength multiplexing station and said path changing station respectively control the power of the optical signals of the respective wavelengths included in said wavelength division multiplexed light, comprising an information communication unit which communicates a signal including information relating to the control state of the power of the optical signals of the respective wavelengths included in said wavelength division multiplexed light, between said wavelength multiplexing station and said path changing station, and said path changing station executes control of the power of the optical signals of the respective wavelengths in its own station, after having determined the completion of control of the power of the optical signals of the respective wavelengths in other stations located on the upstream side of its own station, based on information obtained by said information communication unit, wherein said path changing station has: an optical signal power controller which controls the power of optical signa 1 s of the respective wavelengths included in said wavelength division multiplexed light, based on information obtained by said information communication unit; a connection destination database in which information related to connection destination of the optical path of the optical signals of the respective wavelengths included in said wavelength division multiplexed light is stored in advance; and an information transfer controller which refers to said connection destination database, and of the information obtained by said information communication unit, transfers only information corresponding to the wavelength for which connection of said optical path is performed directly in the state of light, to said optical signal power controller.