Patent ID: 7529480

Claim:
A method for monitoring lightpaths in an optical network comprising a plurality of optical nodes, each associated with a respective nodal identifier, said optical nodes interconnected by wavelength-multiplexed links and exchanging control signals through a control network, the method comprising the steps of: modulating an optical signal of each lightpath by an identifying optical signature; storing at each optical node: identifiers of optical signatures of specific lightpaths designated to traverse said each optical node; identifiers of adjacent optical nodes designated to be along each lightpath from among said specific lightpaths: and identifiers of optical signatures detected at said each optical node; selecting, by a command-line interface communicatively coupled to a start optical node, a target lightpath connecting a source optical node to a destination optical node and traversing said start optical node; determining, by said command-line interface, a target optical signature stored at said start optical node and associated with said target lightpath; progressively communicating a first message comprising said target optical signature to adjacent optical nodes to determine a first sequence of optical nodes designated to form said target lightpath; progressively communicating a second message comprising said target optical signature to adjacent optical nodes to determine a second sequence of optical nodes actually receiving said target optical signature; and comparing said second sequence to said first sequence; and wherein the steps of determining, progressively communicating the first message, progressively communicating the second message, and comparing are performed without interacting with a centralized network management system.