SRMAC: Staggered Routing-Enhanced MAC Protocol for Wireless Sensor Networks

In Wireless Sensor Network MAC protocol designs, end to end latency is a field that many researches often focus on. RMAC[1], as a synchronizing MAC protocol, shows great advantage in reducing end to end latency than other MAC protocols. However, the performance of RMAC degenerates when encountered with interference hotspots. In this paper, we present an enhanced MAC protocol called SRMAC, which is derived from RMAC. Unlike RMAC and some other derivative MAC protocols such as PRMAC[2] and Bulk MAC[3], SRMAC is designed to alleviate the performance degradation incurred by interference hotspots. With little overhead, SRMAC staggers different flows and let them propagate through these hotspots in the same cycle. Some specific mechanisms are employed to realize this function and avoid potential collision. We evaluate its performance by NS 2.29 and compare the simulation result with that of RMAC. The result indicates that SRMAC performs better than RMAC distinctively in hotspot scenarios. The delay incurred by interference has been alleviated.