Comparative Account of Bandwidth Efficiency in Optical Burst Switching and Optical Circuit Switching Networks

The performance of Optical Burst Switched (OBS) networks is compared to that of Optical Circuit Switched (OCS) networks in terms of bandwidth efficiency. Two traffic flow models are employed to investigate the effects of traffic grooming, packetization, buffering and burst assembly on bandwidth efficiency and utilization. Traffic is represented by fluid-flow continuous bit streams in the first model and by packet-based discrete flows in the second model. It is shown that the parameters of traffic characteristics and burst assembly have significant impact on the relative bandwidth savings of OBS. The bandwidth efficiency of OBS compared to OCS should not be taken for granted and has to be examined carefully on a case by case basis.