Dynamic reconfiguration policies for WDM networks

We study the issues arising when considering the problem of reconfiguring broadcast optical networks in response to changes in the traffic patterns. Although the ability to dynamically optimize the network under changing traffic conditions has been recognized as one of the key features of multiwavelength optical networks, this is the first in-depth study of the tradeoffs involved in carrying out the reconfiguration process. We first identify the degree of load balancing and the number of retunings as two important, albeit conflicting, objectives in the design of reconfiguration policies. We then formulate the problem as a Markovian decision process and we develop a systematic and flexible framework in which to study reconfiguration policies. We apply results from Markov decision process theory to obtain optimal reconfiguration policies for networks of large size. The advantages of optimal policies over a class of threshold-bused policies are illustrated through numerical results.