Scalable elastic optical path networking models

Abstract

In order to face the steady growth of the optical networks, network operators are now moving to elastic optical networking, with the challenge of optimizing the spectrum usage through the so-called routing and spectrum assignment (RSA) problem. It is a much more difficult problem than the classical routing and wavelength assignment (RWA) problem, for which practical algorithms are now available for solving realistic data instances. Several authors have already investigated the routing and spectrum assignment problem, with either heuristics or exact algorithms. However, there is still a gap between the size of the instances that can be solved using those algorithms, and the sizes of the industry RSA instances. The objective of this study is to reduce the gap between the two, using a new mathematical modelling, and to compare its performance with the best previous algorithms/models on various realistic data instances.