Design of virtual topologies for large optical networks through an efficient MILP formulation

In this paper we propose a Mixed-Integer Linear Programming (MILP) formulation for designing virtual topologies of wavelength-routed optical networks, considering as objective function the minimization of the traffic electronically forwarded at the network nodes. Our goal is twofold. Firstly, to reduce packet router processing requirements of the electronic routers, and secondly, to get the most transparent traffic distribution for a given traffic matrix, using the available optical resources at the nodes. The proposed formulation was applied successfully to reasonable sized networks yielding optimal solutions in a few minutes. To the best knowledge of the authors, this is the first report on optimizing virtual topology and traffic routing of large optical networks with a low computational cost MILP formulation.