A comprehensive study of IoT and WSN MAC protocols : research issues, challenges and opportunities

Recent advances in wireless technologies, micro-electro-mechanical systems, and embedded systems enable the popular usage of the Internet of Things (IoT) and wireless sensor networks (WSNs) in many important applications, such as smart buildings, security, target tracking, industrial automation, and so on. Typically, a WSN consists of a large number of tiny, low-cost sensor nodes that are limited in terms of their capabilities of computation, communication, memory, and power. In WSNs, energy-efficient algorithms are of paramount importance for a long lasting high throughput network. MAC protocol plays a prominent role in extending the life-time of WSNs. MAC protocols provide various schemes on how multiple nodes access a common wireless medium. To achieve a longer lifetime for the nodes and the networks, MAC protocols need to be energy-efficient and reduce the sources of energy wastage. Energy conservation in sensor nodes is generally achieved by duty cycling the radios, and it is the MAC layer protocol that controls when to switch on and off the radio. In this paper, we discuss the essential properties of MAC protocols, the MAC for IoT and the common causes of energy consumptions. Thereafter, we categorize the MAC layer protocols and discuss several protocols under each category in depth, emphasizing their strengths and weaknesses, and giving a detailed comparison of MAC protocols. Finally, we conclude the survey with the insights on future research directions.EDB (Economic Devt. Board, S’pore)Published versio