A method for establishing an embedded optical communication channel in an optical WDM transmission system including: creating, at the central network device, a broad-band optical signal, supplying the broadband optical signal, transmitting the broadband optical signal and the plurality of second optical channel signals to an optical demultiplexer device, transmitting an optical signal consisting of a dedicated second optical channel signal and a filtered broadband optical signal; receiving the optical signal and creating a corresponding electrical receive signal and extracting the electrical signal corresponding to the filtered broadband optical signal from the electrical receive signal and detecting whether the electrical signal contains information intended for the respective first channel transceiver.