Ultrafast optical packet switching over arbitrary physical topologies using the Manhattan Street Network

immature nature of optical logic devices and the limitations associated with optical buffering provide significant incentive to reduce the routing complexity and avoid optical domain contentions. This paper examines how the Manhattan Street Network (MSN) may be used to facilitate optical packet switching over arbitrary physical topologies. Several pertinent novel costs are introduced. Simulated annealing is used to deploy the MSN (near) optimally as a virtual topology in the physical topologies. Favourable and encouraging results are obtained, indicating that deploying the MSN is an attractive means to switch packets optically over arbitrary topologies. I. INTRODUCTION Attempts are being made to reduce the routing processing undertaken at routers in the Internet. The incentive to reduce the algorithmic processing undertaken for routing is even more pronounced when attempting to control data packet switching optically. Compared to electronic devices, optical logic devices are faster [1] but are relatively primitive. Hence, the routing processing needs to be as simple as possible to be executed " on the fly " in the optical domain. A key additional constraint when optically switching packets is the need to avoid or minimise contention in the optical domain due to the non-existence of static random-access optical memory devices and the limited scalability of travelling-wave optical buffers. However, it is often the case that real-life (hence arbitrary) physical topologies necessitate complex routing schemes and the need for buffers to resolve any resultant contentions.