Priority scheme for supporting quality of service in optical burst switching networks

Feature Issue on Optical Interconnection Networks (OIN) We present what we believe to be a new scheme, called preemptive prioritized just enough time (PPJET), for quality-of-service (QoS) provisioning in bufferless optical burst switching (OBS) networks. PPJET provides better service for high-priority traffic by dropping reservations belonging to lower-priority traffic with a new channel-scheduling algorithm called preemptive latest-available unused channel with void filling (PLAUC-VF). An approximate method for calculating the dropping probability in PPJET is also discussed. Moreover, we perform discrete-event simulations to evaluate the performance of PPJET. Simulation results show that PPJET outperforms offset-based QoS schemes both in terms of dropping probability and end-to-end delay.