Abstract
In this paper, we investigate adaptive routing in wavelength-routed networks. Exploiting the concept of load balancing, we propose an adaptive routing strategy named weighted-shortest-cost-path (WSCP). The salient feature of WSCP is that it seeks the path that minimizes the resource cost while simultaneously maintaining the traffic load as balanced as possible. We compare the blocking probability and average hops of WSCP with traditional shortest-cost-path (SCP) strategy, fixed routing, and alternate routing. The numerical results show that WSCP can enhance blocking performance and just lengthen hop distances a little longer. The improvement is more significant in denser networks or with more wavelengths. We also develop an analytical model to estimate blocking performance of WSCP.