Wireless Sensor Network Mac Protocol

An emerging technology, the wireless sensor network, has a wide range of potential applications including environment monitoring, smart spaces, medical systems and robotic exploration. Medium Access Control (MAC) protocol which is loaded at the base layer of the wireless sensor network architecture directly controls the way of the nodes using the wireless channel, so designing suitable MAC protocol is very important for wireless sensor networks to improve efficiency and extend life-time.First, in this paper, the structure, characteristics and applications of wireless sensor networks have been introduced briefly. Then typical protocols of all classes MAC protocol for wireless sensor networks have been analyzed and compared. Afterwards, to reduce the energy consumption, an improved MAC protocol with anti-attack capacity for wireless sensor network—a hybrid MAC protocol combined with CSMA and TDMA(named SCT-MAC for short), has been proposed, which is based on the IEEE 802.11 and S-MAC(Sensor-MAC) protocol,and added the TDMA mechanism and anti-attack module. Based on this MAC protocol, wireless sensor network can work on less energy-consumption and quickly recognize the attack behavior and keep its normal operation when it encounters attack in complex environment. And then, an energy-efficiency model has been presented, with which IEEE802.11, S-MAC and SCT-MAC were compared. Finally, the improved MAC protocol has been simulated on J-Sim, which is a novel simulation environment for wireless sensor network. In this simulation, energy consumption and anti-attack performance have been tested. The result shows that the improved MAC protocol consumes less energy than IEEE 802.11 protocol and S-MAC protocol in the same environments, and the signal noise ratio of the nodes and the throughput of the network will recover rapidly when the network is suffering malicious attack.