Adaptive Wavelength Assignment Scheme for Distributed Path Restoration in Optical Networks

In wavelength-routed optical networks, routing and wavelength assignment (RWA) can be implemented in a dynamic and distributed way. During the distributed restoration process after a failure occurs, the concurrent reservation attempts from different original nodes may lead to collisions because they select the same wavelength with a large possibility, resulting in high recovery blocking probabilities. This paper presents a contention avoidance mechanism to improve restoration performance. With the adaptive wavelength assignment method, reservation contentions between adjacent nodes are reduced significantly and higher recovery ratio is achieved.