Routing and wavelength assignment with power considerations in optical networks

Previous studies have solved many variations of the routing and wavelength assignment (RWA) problem in optical networks under the assumption of perfec t conditions regarding the power of a signal. In this paper, we investigate the RWA problem while allowing for degradation of routed signals by optica l components. The problem is formulated as a mixed-integer non-linear progr am. We propose a two-phase approach. In the first phase, we solve the pure RWA problem using fixed routes for every connection. In the second phase, p ower assignment is accomplished by either using a heuristic or using a gene tic algorithm. This paper demonstrates that: (i) connections do interact af fecting the power of each other, and (ii) global search meta-heuristics pro vide better solutions. (C) 2000 Elsevier Science B.V. All rights reserved.