Analysis of Delay Variation with Burst Size In Optical Burst Switching In the Presence of Aggregate Self-Similar Traffic

Considering that optical networking is still in early stages of its evolution, Optical Burst Switching (OBS) is widely recognized as the most feasible data forwarding mechanism for the next generation Optical Internet that could be realized using currently available optical technology. OBS forwards data in a form of bursts of packets assembled and disassembled in the electrical domain in order to overcome the barrier of non-availability of optical memory. The purpose of this paper is to highlight the adverse effects of higher burst sizes on queue delay in the electrical domain in the presence of aggregate self-similar traffic, as that is found in a Differentiated Service (DiffServ) environment. Absolute effects on delay are highlighted by not using packet policing mechanism, similar to a token bucket, at the entrance of a network. This paper presents a combination of analytical and simulated results in verifying additional delays incur, and confirms them for all levels of aggregation and class-based (aggregate) utilization. In short, limitations, in general, in using larger burst sizes, which could deteriorate service quality, in an aforementioned environment, are emphasized. Keywords—optical burst switching (OBS), self-similar traffic, quality of service, differentiated services architecture I