Performance Analysis of Deflection Routing in Optical Burst-Switched Networks

This paper concerns itself with the performance of deflection routing in optical burst-switched networks based on Just-Enough-Time (JET) signaling. Generally speaking, buffer requirement is not vital for JET-based optical burst switching (OBS). However, if deflection routing is enabled, optical buffers are necessary to solve the insufficient offset time problem. A variant of priority queuing model is proposed to approximate burst loss probability and the results show that the model provides an accurate estimation. We also evaluate the performance of deflection routing in arpanet-2 topology. Simulation results indicate that deflection routing evidently brings significant blocking performance gain, especially with fewer wavelengths and under lighter load. In addition, we notice that excessive deflection will cause longer end-to-end delay and reduce the blocking performance. Therefore, it is necessary to control the maximum allowed deflection occurrences of a burst.