Patent ID: 8412038
Filing Date: 2013-04-02
Classification: H04J

Abstract:
1. An optical transmission device comprising: a wavelength multiplexing/demultiplexing unit operable to multiplex a plurality of optical signals of different wavelengths from a plurality of first client devices, respectively, into a first wavelength division multiplexing (WDM) signal and to transmit the first WDM signal to a transmission line, and to demultiplex a second WDM signal received from the transmission line into a plurality of optical signals of respective wavelengths from a plurality of second client devices, respectively, that had been multiplexed into the second WDM signal, each of the first client devices having a priority order; a plurality of transponders for converting wavelengths of the optical signals from the plurality of first client devices, respectively, to provide the wavelength multiplexing/demultiplexing unit with the wavelength-converted optical signals to be multiplexed into the first WDM signal, and converting wavelengths of the optical signals from the second plurality of client devices, respectively, in the second WDM signal after being demultiplexed by the wavelength multiplexing/demultiplexing unit; an optical switch unit for switching connection paths between the transponders and the first client devices; and wherein, when the optical signal provided from the wavelength multiplexing/demultiplexing unit is irregular on the label-changed transponder after the label-changed transponder provides the wavelength multiplexing/demultiplexing unit with the optical signal including the rewritten transmission label, the controller restores the transmission label of the label-changed transponder to the transmission label before being rewritten in the table, and switches the optical switch unit so as to connect the transponder for which the transmission label has been restored to the transmission label before being rewritten to the client device connected to the transponder that received the irregular optical signal.