Abstract: SMAC protocol for wireless sensor network can not adapt to dynamic changes in load, leading to network packet loss and delay jitter,so I}SMAC protocol was designed to solve these problems. Based on packets in the queue waiting time on average the protocol predicts the current network load conditions and dynamically adjusts the duty cycle of nodes,thus achieving efficient use of energy,while ensuring timely and reliable data transmission. The simulation resups show that the improved protocol can effectively use the energy of nodes, ensure the network throughput, lower latency in end-to-end transmission.

Key words: Wireless sensor networks, SMAC, Traffi}adaptive, NS2