An Efficient Hybrid Burst Retransmission and Burst Cloning Scheme Over Star OBS Networks

Optical Burst Switching (OBS) has become a mature technology to support the current and next generation Internet over optical network backbones. In OBS networks contention is the main source of burst loss that can reduce the performance of the higher layers. Burst retransmission is a reactive loss recovery mechanism, which attempts to resolve contention by retransmitting the contended burst at the OBS layer. Burst cloning is a proactive loss recovery mechanism, which attempts to prevent burst loss by sending two copies of the same burst; if the first copy is lost, the second copy may still be able to reach the destination. Burst retransmission is better suited when the load is low, however burst cloning is better suited when the load is high. In order to combines the advantages of burst retransmission at low load with the benefits of burst cloning at high load, we propose a hybrid scheme for star OBS networks that aims to control the extra load due to the both loss recovery mechanisms. Simulation results show that our hybrid scheme can achieve better overall network performance than both burst retransmission scheme and burst cloning scheme.