A Priority-Aware Piggybacking-Based Energy-Efficient MAC Protocol Using Bit Mapping

Battery-powered IoT sensor nodes require energy-efficient Medium Access Control (MAC) protocols to extend network lifetime while supporting priority-sensitive traffic. This paper proposes a Priority-Aware Packet Aggregation/Piggybacking-Based (Priority + Packet Aggregation) Hybrid Energy-Efficient MAC (P2A-HMAC) protocol that integrates bit-mapped priority signaling with lightweight packet aggregation/piggybacking to reduce control overhead. The protocol classifies traffic into emergency, buffer-overflow, priority, and normal categories, providing guaranteed access to delay-sensitive data while minimizing radio activity, idle listening, and contention. A mathematical energy model is developed for both priority- and contention-based operations. MATLAB-based evaluation demonstrates that P2A-HMAC consistently achieves lower energy consumption than TDMA, EA-TDMA, ASHMAC, E-BMA, and P2A-HMAC across varying network sizes, packet sizes, and event-generation probabilities. The proposed protocol provides substantial energy savings, particularly in large-scale and moderate-traffic networks, while maintaining priority-aware communication and QoS, making it suitable for low-power IoT and wireless sensor network applications.