Longitudinal power profile monitoring telemetry enabling self-healing optical networks

Soft failures in optical networks pose a significant challenge, as their detection and localization are notoriously difficult. This often leads to suboptimal mitigation strategies being implemented before the root cause is identified. To address this, the longitudinal power monitoring (LPM) technique has gained significant attention in recent years. LPM leverages information from the coherent receiver to compute the power evolution along the optical path. This paper presents an architecture that integrates the power profile information retrieved from the receiver with the SDN controller. The result is a self-healing optical network capable of locating soft failures in its lightpaths and providing finely tuned reconfigurations to solve them. By developing an OpenConfig-compliant YANG model, we implemented a gNMI streaming mechanism to transmit power profile metrics every 1.5 s from the receiver to the SDN controller. This process utilizes two SDN applications that combine the received data at the controller to finalize the power profile computation and pinpoint the location of soft failures. The architecture’s effectiveness is demonstrated through two scenarios. In the first scenario, the SDN controller accurately identifies and resolves attenuation caused by VOAs strategically placed along a span. In the second scenario, the controller jointly examines the power profiles of two lightpaths to locate a faulty WSS that is causing attenuation in only one of them.