Genetic Algorithm for Joint Routing and Dimensioning of Dynamic WDM Networks

The dynamic operation of WDM networks might lead to significant wavelength savings, when compared with their static counterpart, at the expense of facing nonzero blocking probability. Hence, efficient dimensioning (i.e., determining each link capacity) and control methods are required to operate these networks. Typically, the dimensioning of WDM networks is carried out only after the routing algorithm has been defined. However, this way of designing the network might result in inefficient solutions in terms of wavelength requirements. We propose a novel genetic algorithm to solve the joint routing and dimensioning problem in dynamic WDM networks, with the aim of obtaining a network cost close to minimum while guaranteeing an upper bound on the blocking probability. Used prior to network operation, the algorithm determines which route should be used for each potential connection and also dimensions the number of wavelengths required in each link. The efficiency of the algorithm is validated in ring and mesh topologies, providing wavelength savings of up to 17% when compared with the best existing algorithm to date. Moreover, since the routes provided by the genetic algorithm are stored in routing tables, it also ensures extremely fast on-line network operation.