How simple routing algorithms are good for solving RWA problem in survival optical networks?

Abstract

Since Routing and Wavelength Assignment (RWA) in optical networks is NP-complete problem. Many researches have proposed from simple to complex heuristic algorithms for solving this RWA problem. The shortest path of Dijkstra and sometimes the shortest pair of disjoint paths of Suurballe are used for solving this problem. Such simple heuristic algorithms are usually prejudged as inefficient leading to the conception of complex algorithms. In this paper we analyse quantitatively to see how the simple algorithms of Dijikstra and of Suurballe are good in solving RWA problem in survivable optical networks. The comparisons are made against the optimal solution, when it is available, and against a lower bound, otherwise. The results show that simple algorithms once give solutions, they give very good solutions.