Patent ID: 8831424

Claim:
A method, comprising: in an optical communication network that includes a plurality of interconnected network nodes, storing in each network node, for each communication channel that traverses the node, one or more respective impairment margins with respect to impairments that affect the communication channel, each impairment margin indicating an amount of impairment that the communication channel can tolerate and remain within specified performance criteria; identifying a potential communication channel that traverses a subset of the nodes in the network; and determining a quality of the potential communication channel by evaluating the impairment margins stored in the nodes in the subset, wherein determining the quality comprises evaluating the impairments inflicted on the potential communication channel by at least one other communication channel that traverses at least one of the nodes in the subset using the impairment margins stored in the at least one of the nodes, and evaluating the impairments inflicted by the potential communication channel on at least one other communication channel that traverses at least one of the nodes in the subset using the impairment margins stored in the at least one of the nodes.