An adaptive routing algorithm for wavelength-routed optical networks with a distributed control scheme

For a wavelength-routed network in which connection requests are arriving and departing at high rates, an appropriate control scheme must be implemented to set up lightpaths for each request in a fast and efficient manner. The control scheme, which includes routing and wavelength assignment algorithms, must also be scalable, and should attempt to minimize the number of blocked connections. In this paper, we consider a distributed control scheme which utilizes a new adaptive routing approach called alternate-link routing. In the proposed approach, routing decisions for a lightpath are made adaptively on a hop-by-hop basis by individual nodes in a distributed manner. The scheme does not require the maintenance of any global information. A simulation is developed to analyze blocking performance, and it is shown that the proposed approach outperforms fixed routing and, under certain conditions, also outperforms fixed alternate-path routing.