Abstract: A load-controlling device controlling load on an optical transmission line, the input of which is coupled to an emitting device for modulating with data and multiplexing a plurality of useful wavelengths into a useful optical signal to be transmitted over the transmission line. The load-controlling device includes elements for generating a filler optical signal composed of at least one filler wavelength that is not modulated by data, to be injected into the optical transmission line. The generating elements generate a source optical signal composed of a plurality of wavelengths corresponding to the plurality of wavelengths of the useful optical signal and selects the wavelength of the filler optical signal among the wavelengths of the source optical signal. A control module controls selection of the wavelength of the filler optical signal depending on information indicative of non-turn-on of a wavelength among the plurality of wavelengths of the useful optical signal.

Abstract: A load-controlling device controlling load on an optical transmission line, the input of which is coupled to an emitting device for modulating with data and multiplexing a plurality of useful wavelengths into a useful optical signal to be transmitted over the transmission line. The load-controlling device includes elements for generating a filler optical signal composed of at least one filler wavelength that is not modulated by data, to be injected into the optical transmission line. The generating elements generate a source optical signal composed of a plurality of wavelengths corresponding to the plurality of wavelengths of the useful optical signal and selects the wavelength of the filler optical signal among the wavelengths of the source optical signal. A control module controls selection of the wavelength of the filler optical signal depending on information indicative of non-turn-on of a wavelength among the plurality of wavelengths of the useful optical signal.

Abstract: A method is provided for determining an optical signal to noise ratio of a dual polarization optical signal. The method includes: detecting, in the dual polarization optical signal, a modulation signal which modulates, at at least one low amplitude level that is approximately zero and at a high amplitude level, the dual polarization optical signal, and determining the optical signal to noise ratio from a measurement of the power of the modulation signal.

Abstract: A method is provided for determining an optical signal to noise ratio of a dual polarization optical signal. The method includes: detecting, in the dual polarization optical signal, a modulation signal which modulates, at at least one low amplitude level that is approximately zero and at a high amplitude level, the dual polarization optical signal, and determining the optical signal to noise ratio from a measurement of the power of the modulation signal.

Abstract: A synchronous frame is formed by inserting data in virtual containers that are inserted in the fame. The containers are concatenated with each other. Each concatenated container indicates the total number of containers, and the order number of the particular container. A receiver responsive to the frame delivers to its output only the containers with the indications in the order of the order numbers.