Patent ID: 7536104

Claim:
An optical transmission network, comprising: a concentrator comprising a receiving point; a plurality of stations, each comprising a sending point; an optical interconnection tree linking respective sending points of the stations to the receiving point of the concentrator, said interconnection tree including: a common optical link having a first end coupled to said receiving point and a second end coupled to each of said sending points of the stations via a coupling system, and access links each being associated with a respective station and being a point-to-point link connecting the coupling system to the sending point of a respective station and enabling propagation of optical signals from the respective station to the coupling system in an uplink propagation direction or in an opposite downlink propagation direction, said optical signals each being characterized by an uplink wavelength when propagating in said uplink propagation direction; and an emulator adapted to send auxiliary optical waves at said uplink wavelength and to couple the auxiliary waves into said access links downstream of the coupling system to propagate in said downlink propagation direction; and a control system coupled to said emulator for selectively activating sending of said auxiliary waves to permit only one optical signal of the uplink wavelength to travel in the uplink direction to the coupling system.