Channel protection in WDM mesh networks

With the increased transmission capacity in WDM networks a single failure in the network (like a fiber cut or equipment failure) may result in enormous data loss. Therefore, resilience from a component or optical link failure is essential to provide uninterrupted communication between any two nodes in the network. Several techniques exist to provide reliable services in the occurrence of failures. The most common protection technique involves assigning spare capacity. This study focuses on providing channel protection against single failures for networks with or without wavelength converters. In this study a new protection technique is introduced based on the 1:N spare capacity assignment and has been incorporated in RWANCO (Routing and Wavelength Assignment and Network Cost Optimization). The method involves changing the protection wavelength after each failure. Also, the study investigates the effect of this changing wavelength, which introduces some blocking in the network. We also evaluate the protection switching time for the different cases.