A decision algorithm for efficient hybrid burst retransmission and burst cloning scheme over star OBS networks

In optical burst switched networks contention is the main source of burst loss. Burst retransmission is a reactive loss recovery mechanism that attempts to resolve contention by retransmitting the contended burst at the optical burst switching layer. Burst cloning is a proactive loss recovery mechanism that 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 this paper, we propose a hybrid scheme for star OBS networks that combines the advantages of burst retransmission at low load with the benefits of burst cloning at high load through a decision algorithm which aims to control the extra load due to the both loss recovery mechanisms. The results obtained from simulation confirm that our hybrid scheme through the decision algorithm can achieve better overall network performance than both burst retransmission scheme and burst cloning scheme.