Delay efficient MAC protocol for Diffusion based routing in Wireless Sensor Networks

In this paper we present DESMAC a contention based Medium Access Control protocol for Diffusion based routing in Wireless Sensor Networks. One of the main challenges in WSNs is to balance delay efficiency and energy consumption. Surveillance and monitoring application as well as many other need low latency data delivery; but, since sensor nodes have a small source of energy usually Active/Sleep cycles are used to reduce the energy consumption which causes higher delay. We use routing information to adaptively change the duty cycle for different loads. In our Cross Layer Design the Routing Layer can manipulate the duty cycle of underlying MAC protocol. The diffusion control messages are used to adapt the duty cycle to variation in the load. Also extensive use of some nodes can damage the connectivity of network. Therefore we provide a mechanism to balance the load between several possible paths. We discuss DESMAC design and compare our Simulation results to S-MAC and IEEE 802.11 standard. DESMAC achieves significant latency reduction (Lip to 50 times better delay than S-MAC) while ensuring energy efficiency and load balanced delivery.