Contention-based traffic priority MAC protocols in wireless body area networks: A thematic review

Wireless Body Area Networks (WBANs) healthcare application is a group of heterogeneous-natured Bio-Medical Sensor Nodes (BMSNs) used to sense and monitor a patient’s vital signs, in the long run, under natural physiological conditions, without affecting the regular activities. Heterogeneous-natured BMSNs demand prioritized channel access during contention access phases to transmit data or allocate time slots in contention-free phases. Thus, contention-based prioritization of heterogeneous traffic is required in WBANs. Therefore, many researchers have considered and presented various traffic-priority Medium Access Control (MAC) protocols. This paper provides a thematic review of contention-based traffic priority MAC protocols in WBANs. Slotted Carrier Sense Multiple Access / Collision Avoidance (CSMA/CA) scheme in beacon-enabled modes of IEEE 802.15.4 and IEEE 802.15.6 MACs is also analyzed regarding contention-based traffic prioritization. In addition, a critical and comparative analysis of existing contention-based traffic priority MAC protocols is obtained. A hierarchy of contention-based traffic priority MAC protocols is proposed. This review on contention-based traffic priority MAC protocols in WBANs extends the body of knowledge. This paper, therefore, serves as the first and enhances the concept of contention-based traffic prioritization at the MAC layer in WBANs. We have confidence that this paper will stimulate a better way of solving the contention-based traffic prioritization problem.