An RWA Algorithm for OBS Networks based on Iterative Local Optimization of Total Blocking Probability

摘要

We propose a routing and wavelength assignment algorithm for Optical Burst Switching (OBS) networks that utilizes centralized control. First, a method that can estimate the expected total blocking time in the network is presented. Then the proposed algorithm minimizes the estimated blocking time by simple iterative local optimization in terms of the traffic demand between each pair of nodes. We demonstrate that the proposed algorithm attains much smaller blocking probability than conventional distributed control algorithms. It is also shown that with introduction of optical buffers and burst retransmission, the proposed method realizes low burst loss rates ( < 10~(-6)) acceptable for most applications.