Abstract: A system and method is disclosed that detects the onset of failing optical subnetwork network elements and minimizes the volume of Performance Monitoring (PM) parameter data that must be acquired and trend across a provisioned path by monitoring digital (SONET/SDH) section PM parameter data first, which is used to trigger an examination to determine which optical subnetwork is experiencing degradation. Threshold Crossing Alerts (TCAs) are set for digital section PM parameter data and when a digital section PM parameter is greater than or equal to its TCA, the method identifies which subnetwork is degrading. Once a subnetwork is identified, analog PM parameter data is acquired for network elements employed in the identified subnetwork and determines from monitoring the network elements' analog PM parameter data the network element(s) that is degrading. A maintenance ticket is issued identifying the failing network element(s).