Improving the Performance of All-optical WDM Networks based on Light-path Reservation

Abstract

In this paper, three methods are proposed to improve the performance of all-optical WDM networks based on the light-path reservation scheme. These are wavelength conversion, multiple fibers and two-path routing. We begin by developing analytical models for static-routing networks based on the nonblocking centralized switch, bi-directional Manhattan Street network and de Bruijn network topologies. Analytical results show that in most cases, the multiple fibers and wavelength conversion schemes give the best performance, in terms of lowest blocking probability, for the nonblocking centralized network at light and heavy loads respectively. The reverse is true for the bi-directional Manhattan Street and de Bruijn networks. The choice depends on the values of the parameters such as network load and reservation level. The two-path routing method offers moderate improvement in performance for the de Bruijn network topology. In addition, there exist optimum reservation levels for attaining minimum blocking probabilities. The advantage of the three schemes is moderate in the centralized switch, and slightly less in the de Bruijn network. However, these schemes offer significant performance improvement for the bidirectional Manhattan Street network.