The optimization of S-MAC based on traffic adaptation
Hong Xie · Applied science and technology · 2011
sensor-MAC(S-MAC) is a classic MAC protocol based on competition for wireless sensor networks(WSN).The protocol adopts interception and sleep mechanism with fixed duty cycle,and the nodes have the same competition window(CW).So it agrees well with the requirements of WSN MAC protocol which should be energy-saving and simple.However,S-MAC can not adapt to the Internet traffic change due to the fixed duty cycle and CW.The queue information is introduced to judge the size of traffic and optimize S-MAC protocol.When the traffic is heavy,modify sleep time to adjust the duty cycle.And the CW adjustment algorithm is added to reduce probability of collision when the traffic is heavy,thereby increasing efficiency.The simulation results on NS2 show that when the traffic is heavy the proposed optimization protocol has better performance.