Off-line algorithms for Routing, Modulation Level, and Spectrum Assignment in elastic optical networks

Optical network architectures with elastic bandwidth provisioning are a very promising approach for next generation optical networks. Such elastic optical networks will enable efficient resource utilization and flexible sub-wavelength and super-channel connection provisioning to support heterogeneous and immense bandwidth demands. In this paper, we focus on the problem of Routing, Modulation Level, and Spectrum Allocation/Assignment (RMLSA) which emerges in such networks. We both formulate RMLSA as an Integer Linear Programming (ILP) problem and propose an effective heuristic method called Adaptive Frequency Assignment - Division and Collision Avoidance (AFA-DCA) to be used if the solution of ILP is not attainable.