BURST SEGMENTATION: A NEW APPROACH TO REDUCE PACKET LOSS IN OPTICAL BURST SWITCHED NETWORKS by

ACKNOWLEDGEMENTS Firstly, I would like to thank my advisor Dr. Jason Jue for giving me the guidance that have been instrumental in shaping my career. But for his invaluable advice and assistance it would not be possible for me to complete this thesis. I would also like to express my gratitude to Dr. Balaji Raghavachari and Dr. Gopal Gupta for giving me the opportunity to work with them as a research assistant for the past year, in the Telecommunication Laboratory. I would also like to express my gratitude to Dr. Balaji Raghavachari and Dr. S. Q. Zheng for serving on my committee. Also a sincere thanks to all the members of Telecommunication Lab for their encouragements and advice. And most importantly to my parents, my brother and friends, for staying beside me at all times and helping me realize my ambitions. The current fast-growing Internet traffic is demanding more and more network capacity each day. The concept of wavelength-division multiplexing has provided us an opportunity to multiply network capacity. Currently optical switching technologies allow us to rapidly deliver the enormous bandwidth of WDM networks. Optical burst switching offers all-optical, high-speed data rate, format transparent switching, which are essential characteristics needed to support future networks supporting different classes of data. In this report, we analyses a critical issue involved in the optical burst switched networks , namely contention resolution. In existing contention resolution schemes for optical burst switched networks, when contention between two bursts cannot be resolved through other means, one of the bursts will be dropped in its entirety, even though the overlap between the two bursts may be minimal. For certain applications, which have stringent delay v requirements but relaxed packet loss requirements, it may be desirable to lose a few packets from a given burst rather than losing the entire burst. We introduce a new approach called Burst Segmentation, to reduce packet loss during contention resolution. Burst segmentation is also analysed in conjunction with deflection routing to reduce packet loss during contention. We also introduce two ways of resolving contention namely, Deflect-First policy and Segment-First policy. In burst seg-mentation, rather than dropping the entire burst during contention, the burst may be broken into multiple segments, and only the overlapping segments during contention are dropped. Through simulation, it is shown that segmentation policy reduces packet loss substantially when compared to the standard policy of dropping the contenting burst in …