New optical burst switching protocol for supporting quality of service

Optical burst switching (OBS) is a new paradigm proposed to efficiently support the ever-growing broadband multimedia traffic either directly or indirectly (e.g., via IP) over all optical WDM networks. In this paper, we propose a new prioritized OBS protocol based on Just-Enough-Time (JET) which can provide Quality of Service (QoS) in buffer-less WDM optical networks. Specifically, we apply OBS to support two traffic classes: real-time and non-real-lime, such that each burst belonging to the former is assigned a higher priority by simply using an additional offset time between the burst and its corresponding control (set-up) packet. We analyze the lower and upper bounds on the blocking probability of each traffic class, and evaluate the performance of the proposed prioritized OBS protocol through analysis and simulation. We show that real-time traffic can achieve a significantly reduced blocking probability by using a reasonable amount of additional offset time. In addition, the overall blocking probability and throughput can be maintained regardless of the additional offset time used.