The disclosure includes an apparatus comprising: a path computation element (PCE) comprising a processor configured to: receive a path computation element protocol (PCEP) path computation request from a path computation client (PCC), wherein the path computation request comprises an impairment validation request that directs the PCE to perform an impairment validation of a network path; after receiving the path computation request, compute a network path; and perform an impairment validation of the network path specified by the impairment validation request. In another embodiment, the disclosure includes a method comprising: sending, by a PCC a PCEP path computation request to a PCE, wherein the request directs the PCE to perform routing and wavelength assignment (RWA) and a first impairment validation of a network path, wherein the request comprises a type of signal quality of the network path which indicates the first type of impairment validation to be performed.