Adaptive weight functions for shortest path routing algorithms for multi-wavelength optical WDM networks

Optical dense wavelength division multiplexed (DWDM) networks are an attractive candidate for the next generation Internet and beyond. In this paper, we consider the wide area wavelength routed backbone network with circuit-switching. Given a session request, the routing and wavelength assignment (RWA) problem is to calculate a path between two nodes, and also assign a set of wavelengths along this path. We use Dijkstra´s shortest path algorithm, suitably modified for DWDM networks, for computing the shortest paths. We consider WDM aware weight functions which include factors such as available wavelengths per link, distance, and total wavelengths per link. We study and compare the performance of these weight functions in terms of blocking probability, link utilization and average delay