PR-CCA MAC: A Prioritized Random CCA MAC Protocol for Mission-Critical IoT Applications

A fundamental challenge in Mission-Critical Internet of Things (MC-IoT) is to provide reliable and timely delivery of the unpredictable critical traffic. In this paper, we propose an efficient prioritized Medium Access Control (MAC) protocol for Wireless Sensor Networks (WSNs) in MC-IoT control applications. The proposed protocol utilizes a random Clear Channel Assessment (CCA)-based channel access mechanism to handle the simultaneous transmissions of critical data and to reduce the collision probability between the contending nodes, which in turn decreases the transmission latency. We develop a Discrete-Time Markov Chain (DTMC) model to evaluate the performance of the proposed protocol analytically in terms of the expected delay and throughput. The obtained results show that the proposed protocol can enhance the performance of the WirelessHART standard by 80% and 190% in terms of latency and throughput, respectively along with better transmission reliability.