Optical layer status exchange over OSC-OAM method for ROADM networks

A method comprising the steps of:

• receiving, by circuitry of an optical node adapted for wavelength multiplexing and wavelength switching, a signal over an optical control channel, the signal conforms to an optical carrier (OC-N) frame format, and the signal includes a transport overhead portion of a synchronous transport signal frame format, the transport overhead portion including D4-D12 bytes, a first one of the D4-D12 bytes including first bits of a Backward Defect Indication Payload field, second bits of a Backward Defect Indication Overhead field, and third bits of a Payload Missing Indicator field, the first bits, the second bits, and the third bits being indicative of a status of an optical layer in an optical transport network, a second one of the D4-D12 bytes including the first bits, the second bits, and the third bits, and a third one of the D4-D12 bytes carrying the first bits, the second bits, and the third bits;
• receiving, with the interfaces, wavelength division multiplexed optical signals;
• terminating, by circuitry of the optical node, the signal at the optical node;
• and
• notifying, by circuitry of the optical node, software of the status of the optical layer in the optical transport network based on at least one of the D4-D12 bytes.

A network that complies with an Optical Transport Network, the network, comprising:

• a plurality of nodes, one of the plurality of nodes receiving a signal over an optical control channel, the signal conforms to an optical carrier (OC-N) frame format, and the signal includes a transport overhead portion of a synchronous transport signal frame format, the transport overhead portion including D4-D12 bytes, a first one of the D4-D12 bytes including first bits of a Backward Defect Indication Payload field, second bits of a Backward Defect Indication Overhead field, and third bits of a Payload Missing Indicator field, the first bits, the second bits, and the third bits being indicative of a status of an optical layer in an optical transport network, a second one of the D4-D12 bytes including the first bits, the second bits, and the third bits, and a third one of the D4-D12 bytes carrying the first bits, the second bits, and the third bits;
• wherein the optical carrier frame format comprising a first synchronous transport signal frame, a second synchronous transport signal frame, and a third synchronous transport signal frame, the synchronous transport signal frames having a synchronous transport signal frame format;
• said one of the plurality of nodes further including circuitry that terminates the signal at the optical node, and circuitry notifies software of the status of the optical layer in the Optical Transport Network based on the D4-D12 bytes.