On Protecting Link Failure of Wavelength Routed Mesh Network

The Dense Wavelength Division Multiplexing (DWDM) is the most cost-effective way to upgrade the optical links to the wavelength-routed optical network, while each link can carry a certain number of wavelengths. The mesh is recognized as the topology to serve the optical networks since it has higher reliability and requires lower spare bandwidth. To decide whether a wavelength-routed mesh network with W wavelengths can support a set of requests has been shown to be NP complete. To consider rerouting the requests on the single link failure makes the problem even harder. This paper proposes polynomial-time approximation algorithms for this problem. The performance ratio of the approximation is also being analyzed.