Patent ID: 7336901

Claim:
A reconfigurable optical add-drop multiplexer (ROADM) supporting Optical Multiplex Section shared protection with loopback switching, comprising: a first optical supervisory module, comprising: a Westln port for receiving a multichannel signal comprising a first set of Optical Channels; a 2×1 switch having a first input, a second input, and an output, the first input for receiving a Westln optical signal, a second input for receiving a small fraction of a loopback copy of an outgoing Optical Multiplex Section, the loopback copy comprising the multichannel signal having the first set of Optical Channels, the 2×1 switch selecting either the first input or the second input for generating to the output of the 2×1 switch; an optical tap having an input, a first output, and a second output, the optical tap tapping a portion of the multichannel signal that is used to determine the presence or absence of an incoming signal to the first output, the first output of the optical tap coupled to the second input of the 2×1 switch; an 1×1 switch having an input coupled to the output of the second output of the optical tap and output; a WestOut port coupled to the output of the 1×1 switch: an amplifier module having an input coupled to the output of the 2×1 module, and an output; and a broadcast and select module having a first input coupled to the output of the amplifier module, a second input, and an output coupled to the input of the optical tap.