SC-MAC: A sender-centric asynchronous MAC protocol for burst traffic in wireless sensor networks

Event-driven applications in wireless sensor networks feature correlated traffic bursts: after a period of idle time with light traffic loads, multiple sensors that have detected the same event have to transmit large amounts of data simultaneously to sink node or cluster head. The demand for simultaneous data transmission often causes severe collision, which is one of the most significant sources of energy consumption in wireless sensor networks. In this paper, we propose SC-MAC (sender-centric MAC), a new asynchronous duty cycle MAC protocol designed for burst traffic loads. SC-MAC achieves collision-free environment while do not introduce extra overhead. In order to minimize delivery latency in tree structure or other multi-hop networks, SC-MAC also introduces a latency optimization mechanism. We show the performance of SC-MAC through ns-2 simulation and compare it to PW-MAC, the state-of-the-art asynchronous MAC protocol. The simulation results show that SC-MAC significantly minimizes energy consumption and delivery latency.