Off-line configuration of an MPLS over WDM Network under time-varying offered traffic

Coupling MPLS Traffic Engineering on top of a wavelength-routed WDM layer offersgreat flexibility to operatorsto allocate traffic demandsin their networks. In this paper we consider the problem of off-line joint configuration at both packet and optical layers. We consider time-variant offered traffic, and assume that the operator has knowledge of the traffic dynamicsasa set of traffic matricesat different instants. A novel Mixed Integer Linear Programming (MILP) formulation isprop osed, which takesin input this set of traffic matrices, and provide an optimal static configuration capable of accomodating the time-varying traffic. We provide a resolution strategy based on heuristics, and give numerical results for some sample cases. The proposed method iscompared with a simple alternative approach for obtaining a single static solution, to show that our method utilizes much less resources. The solution under the proposed formulation is also compared with the set of solutions obtained by running distinct optimization problems at different instants, showing that the increase of resource is minimal. Hence our approach can provide a static configuration with about the same resources of a fully adaptable dynamical configuration.