GA-based dynamic survivable routing in WDM optical networks with shared backup paths

This paper considers the problem of dynamic survivable routing in WDM networks with single link failure model. This work mainly concerns in how to dynamically determine a protection cycle (i.e., two link-disjoint paths between a node pair) to establish a dependable lightpath with backup paths sharing. The problem is identified as NP-complete, thus a heuristic for finding near optimal solution with reasonable computation time is usually preferred. Inspired from the principle of genetic algorithms (GA), a GA-based survivable routing algorithm for the problem with a new fitness function, which allows us to improve blocking performance, will be proposed. Extensive simulation results upon the ns-2 network simulator and two typical network topologies show that our algorithm can achieve a significantly lower blocking probability than conventional algorithms.