A method configuring an optical transmission interface of at least one first device transmitting optical signals on a path to a second device on a carrier wavelength substantially equal to a nominal wavelength of an optical band-pass filter present on the path, each first device including an optical reception interface to enable receiving optical signals from the second device, the second device including an optical reception interface to enable receiving optical signals output by the first optical band-pass filter and transmitted by any first device on a carrier wavelength substantially equal to the nominal wavelength, the optical transmission interface of each first device being initially configured for transmitting optical signals on a first carrier wavelength.