Energy-Efficient MAC Protocols for Wireless Sensor Networks

This chapter addressed MAC layer protocols for WSNs from a broad perspective, ranging from static, single-channel MAC protocols to multi-channel approaches and protocols able to support mobility. While the MAC protocols are usually grouped into two main categories, schedule-based and contention-based, we found that a number of MAC protocols for WSNs actually try to combine the advantages of both classes in order to cope with the conflicting requirements of WSNs, such as energy efficiency, scalability, timeliness, adaptability, and fault tolerance. Several MAC protocols in the literature are overviewed in this chapter, to give an idea of the problems addressed, of the techniques used and the performance obtained by these solutions. Classical approaches as well as novel trends, such as the use of spatial correlation to enhance energy efficiency, are discussed.