On the complexity of routing and spectrum allocation in survivable elastic optical network with unicast and anycast traffic

Abstract

In this paper, we focus on the routing and spectrum allocation (RSA) problem in survivable elastic optical networks (EONs) with unicast and anycast traffic demands. We study a number of problem versions which differ in the involved technological constraints and facilities entailed by the EON technology, as well as, in the applied protection scheme, namely, either dedicated path protection (DPP) or shared backup path protection (SBPP). Each problem version is formulated by means of two integer linear programming (ILP) models: slice-based and channel-based. Next, we analyse the problem complexity (in terms of the number of variables, constraints and processing time) when different technological options for the EON realization are assumed. Eventually, we discuss the slice-based and channel-based modelling approaches in terms of their impact on the ILP formulation complexity, as well as, possibility and ease to adapt to different problem versions.