简介:Aquality-of-service(QoS)awarescheme,calledprecautionaryperformancemonitoring,isproposedtosolvetheopticalimpairmentsandcongestioncontrolincoherentopticalorthogonalfrequencydivisionmultiplexed(CO-OFDM)networks.Thecentralizedpathcomputationelement(PCE)extensionsbasedontheQoSlevelareappliedtoopticalperformancemonitoringinthisletter.