Joint optimization of multicast and unicast flows in elastic optical networks

Nowadays, multicasting is increasingly popular, due to the ability to provision in efficient way such desirable services like streaming, IP television, software distribution, etc. At the same time, the research in the field of optical networks concentrates on the very promising elastic optical networks (EONs) approach. In this paper, we focus on the joint optimization of multicast and unicast flows in EONs. We propose to model multicast flows in EONs using pre-generated candidate trees. We present two new ILP models and a heuristic method, dedicated to solve the optimization problem with joint multicast and unicast flows. We report results of the numerical experiments carried out to compare proposed ILP models and the heuristic method as well as to evaluate potential benefits of multicasting in EONs. We show that the proposed modeling approach and heuristic method are highly elastic in terms of their applicability to different network scenarios, whilst multicasting can bring significant spectrum savings compared to unicasting.