Patent ID: 7936749

Claim:
A method of transferring supervisory control information, the method comprising: wavelength division multiplexing supervisory control information, including wavelength path identification information for uniquely identifying each wavelength path in a network, on a dedicated wavelength and signal light obtained by superposing supervisory control information, including the same wavelength path identification information as in the supervisory control information on the dedicated wavelength, on an optical main signal of each wavelength path, and transferring an obtained wavelength division multiplexed signal; receiving first supervisory control information, including first wavelength path identification information of a first wavelength path and conformance information, multiplexed in a wavelength division multiplexed signal input from one of a plurality of input ports; extracting second supervisory control information, including second wavelength path identification information, superposed on an optical main signal of a second wavelength path from signal light to be multiplexed in a wavelength division multiplexed signal to be output from one of a plurality of output ports; comparing the first wavelength path identification information in the first supervisory control information and the second wavelength path identification information in the second supervisory control information when the conformance information in the first supervisory control information indicates that the first supervisory control information conforms with third supervisory control information, including the first wavelength path identification information, superposed on an optical main signal of signal light of the first wavelength path; and wavelength division multiplexing the first supervisory control information and signal light of the second wavelength path by using the first supervisory control information as supervisory control information on the dedicated wavelength when the first wavelength path identification information matches the second wavelength path identification information, and transmitting an obtained wavelength division multiplexed signal from the one of the plurality of output ports.