Two-layer mesh network optimization based on inter-layer decomposition

Presently, backbone data networks are converging toward a typical two-layer architecture of an IP/MPLS layer over an optical layer. In this paper, we study the problem of maximizing a utility function for an Internet service provider (ISP) of a two-layer mesh networks and propose an efficient decomposition method based on Lagrange relaxation. Differing from previous works on two-layer mesh networks, our proposed decomposition method decomposes an original two-layer mathematic optimization problem, respectively, into an IP/MPLS-layer and an optical-layer optimization problem by slacking the constraints between the two layers. This decomposition method enables to control the trade-off between running time and quality of the feasible solution. Numerical results for a variety of networks indicate that our proposed decomposition method is attractive to quickly find near optimal solutions.