Impact of Burst Control Packet Congestion on Burst Loss Rate in Optical Burst Switched Networks

In the Optical Burst Switching (OBS) research area, the burst control packet (BCP) queuing delay problem has not been addressed because it is believed to be quite small. However, with a realistic OBS simulator, we have investigated this issue and clarified its impact on performance degradation from the point-of-view of data burst loss rate. We know that the BCP load to the control channel is not negligible. Thus, the burst loss rate due to the queueing delay of BCP on the control channel is very serious compared to the existing well-known burst contention. We propose a Dynamic Offset-Time Update scheme to avoid serious data burst loss due to BCP queueing delay, and a Priority BCP queue to guarantee the minimum offset-time for high class bursts. Our simulation results show that the Dynamic Offset-Time Update scheme can completely avoid data burst loss due to BCP congestion while guaranteeing a certain level of minimum offset-time.