Wavelength requirements in wavelength-routed ring networks

In this paper, we discuss the wavelength requirements for wavelength-routed ring networks. A new integer linear programming (ILP) formulation is proposed for routing and wavelength assignment of wavelength path (WP) and virtual wavelength path (VWP) routing schemes. Because the ILP formulation is computationally expensive, an effective heuristic algorithm is also proposed. By using these algorithms, we analyze various network examples with uniform and non-uniform traffic loads. These results will contribute to the optimal usage of wavelength resources in optical networks.