Applications of Computational Intelligence to Impairment-Aware Routing and Wavelength Assignment in Optical Networks

Background

Wavelength routed optical networks have been considered as the most reliable and economic solution to achieve high transmission capacities with Quality of Service (QoS). In these networks, the signal remains in the optical domain between the edge nodes, i.e. the signal propagates along the core of the optical network without any optical-electrical-optical conversion. One of the main challenges in these optical networks is to define an appropriate RWA algorithm in order to obtain a low blocking probability with an acceptable Quality of Transmission (QoT) for every established lightpath. A suitable impairment-aware RWA algorithm has to find a route and select a wavelength between the source-destination nodes that provides a minimum QoT for every network request, taking into account the impairments imposed by the physical layer. Besides, the RWA algorithm needs to consider the efficient utilization of network resources and the optimization of the network performance (Rahbar, 2011; Azodolmolky, 2009; Martinez, 2006).