SN-MAC: a cross layer MAC/Routing algorithm for high-throughput and low-latency WSNs

Energy savings have always been the primary concern in sensor network protocols; however there are applications where latency and throughput are prioritized over energy efficiency and are so significant that the application would not satisfy its requirements without them. Although existing duty-cycle MAC protocols such as SMAC, T-MAC and Z-MAC are power efficient, they introduce significant end-to-end delivery latency and provide poor throughput. In this paper, we propose SNMAC, a CDMA-based power controlled medium access protocol that uses both transmitter based and receiver based CDMA inside a formed cluster, and a TDMA schedule to make the cluster heads communicate with the base station. Our MAC/Routing algorithm targets latency and throughput needs in addition to its ability to increase the overall network lifetime. We discuss the design of SNMAC, and provide a head-to-head comparison with S-MAC focusing on the performance in terms of latency, throughput and energy consumption.