EB-MAC: An event based medium access control for wireless sensor networks

Efficiency in any wireless sensor based application relies significantly on the medium access control it implements. It is not likely that we will see in the near future a unified MAC protocol for wireless sensor networks that is suitable for all wireless sensor applications. In this context, we propose an event based medium access control (EB-MAC) that is tailored for event based systems. Typically, event based systems are characterized by having long periods of inactivity and short abrupt periods of high data contention when an event is detected. High data traffic is generated simultaneously from all sensors detecting the event to deliver captured data. EB-MAC arranges data transfer dynamically using an election based scheduling technique. When data transfer begins, each sensor at a time starts sending data packets in a contention free environment. The protocol is implemented on MicaZ sensor motes where it showed efficiency in reliability, throughput and energy conservation. The algorithm is compared with an implementation of B-MAC with RTS/CTS on MicaZ where it showed its superiority in throughput and latency.