QoS Scheme with Burst Dropping in Optical Burst Switching

We propose a new QoS control scheme by using burst dropping in optical burst switched network. Our proposed scheme consists of Burst Dropping (BD) technique at core nodes and packet arrangement technique at edge nodes. BD technique has been proposed as the effective solution that can improve packet loss at intermediate nodes. By using BD technique, the head of the latter arriving burst are dropped at a burst contention. Our proposed scheme mixes packets of different priorities into a single burst, and arranges them in ascending order of priority at burst assembly. At contention, lower priority packets that are located in former part of a burst are often discarded and higher ones are not often discarded. By computer simulations, we evaluate the QoS performance in terms of packet loss probability and the end-to-end delay performance. As a result, we show that our proposed scheme can provide a basic QoS in terms of packet loss without causing a degradation of end-to-end delay of higher priority packets.