Channel Protection with Real-Time and In-Service Performance Monitoring for Next Generation Secure WDM Networks

Advanced optical networks deploy wavelength division multiplexing technology to transport an unprecedented amount of information per fiber. Each optical channel transports information data rates, typically 2.5, 10 or 40 Gbps. As a consequence, the monitoring frequency and speed of detecting a failure or a severe degradation in conjunction with a fast and intelligent protocol will determine the speed of channel protection and restoration, as well as the speed an intruder is detected. In this paper we present a novel channel self-restoring strategy applicable to optical WDM networks. The performance parameters of each channel such as BER, SNR, Q-factor, NF and signal power in the WDM signal are continuously and un-intrusively monitored. The rate of performance of a channel and the correlation of degradation among the channels in the WDM signal distinguishes between natural degradation or intrusion in an attempt to compromise the security of a channel. When one or more optical channels performance is compromised according to a specific profile, a link-layer proactive protocol triggers a fast switch to channel protection counteracting the compromise. In this paper, we present a real-time and in-service performance estimation mechanism that also detects intrusions and a protocol to remedy failures, degradations, and to countermeasure intrusions.