Dynamic routing in wavelength convertible WDM networks

In wavelength routed WDM networks a routing and wavelength assignment (RWA) algorithm is responsible to make a routing and wavelength assignment decision on the arrival of a lightpath connection request in the network. Both routing and wavelength assignment decisions have a profound effect on the blocking probability of the network or amount of traffic a network can handle under a given load. In this paper we evaluate the blocking performance of some existing routing algorithms (FAR, LLR and WLCR) through simulation techniques. We identify their short comings in wavelength convertible WDM networks and propose a new routing algorithm enhanced WLCR (EWLCR) to overcome the weaknesses of the currently available routing algorithms in wavelength convertible networks. Our simulation results demonstrate that EWLCR performs consistently better in wavelength convertible networks in terms of blocking probability than any of the competing routing algorithms.