Survivable Routing in WDM Weighted Networks

In this paper, we investigate the problem of routing lightpaths on an arbitrary physical topology following a Design Protection approach, such that virtual topology remains connected even after the failure of a single fiber link. This is called survivable routing. It is known to be an NP-complete problem. To address the problem, first, we have proved that embedded Hamiltonian circuit in a mesh network is a must for its survivability. Then using a polynomial time algorithm for generating Hamiltonian circuit i.e. embedded ring virtual topology, we establish lightpaths to the ring. Finally, we design two RWA algorithms to assign lightpaths to other requests in the network, giving priority to wavelength and traffic respectively. We analyze the numerical results obtained for random undirected networks with random normal traffic demands with performance metrics such as maximum one-hop and minimum multi-hop protected traffic, wavelength utilization, number of multi-hops, Buffer size etc.