Comprehensive performance analysis of MAC protocols for wireless sensor networks

Wireless sensor networks (WSNs) are appealing to researchers due to their wide range of application potential in areas such as target detection and tracking, environmental monitoring, industrial process monitoring, and tactical systems. As medium access control (MAC) has a significant effect on the energy consumption, energy efficiency is one of the fundamental research themes in the design of MAC protocols for WSNs. Sensor networks are expected to be deployed in an adhoc fashion, with nodes remaining largely inactive for long time, but becoming suddenly active when something is detected. These characteristics of sensor networks and applications motivate a MAC that is different from traditional wireless MAC such as IEEE 802.11 in several ways. There are plenty of MAC protocols available for WSNs in literature but S-MAC is one of the most popularly used protocol designed specifically for WSN. In this paper, we described an energy-efficient S-MAC protocol, which is a well-known MAC protocol for WSN. The paper presents simulation results of S-MAC performance on a sample sensor node and reveals fundamental tradeoffs on energy, latency and throughput. NS-2 is used for simulation purpose. Results show that S-MAC obtains significant energy savings compared with an 802.11-like MAC without sleeping.