An M/M/1 Preemptive Queue based Priority MAC Protocol for WBSN to Transmit Pilgrims' Data

Every year during Hajj in Saudi Arabia and Kumbh Mela in India, many pilgrims suffering from different medical emergencies thus need real-time and fast healthcare services. Quick healthcare can be facilitated by setting up Wireless Body Sensor Network (WBSN) on pilgrims because of its suitability for a wide range of medical applications. However, higher delay, data loss and excessive energy consumption may occur in the network when multiple emergency data aggregate at the coordinator for accessing the data communication channel simultaneously. In this context, for low delay and energy-efficient data transmission, an M/M/1 preemptive queue technique is proposed and minimal backoff period is considered to develop a priority Medium Access Control (MAC) protocol for WBSN. Our proposed MAC is designed based on IEEE802.15.6 standard that supports modified MAC superframe structure for heterogeneous traffic. The proposed priority MAC protocol has been simulated using the Castalia simulator to analyze the results. In the first scenario considering varying nodes, the delay is calculated as 13 ms and 33 ms for the emergency, and the normal medical condition. Besides, for emergency and normal medical condition energy consumption per bit is calculated at around 0.12 mu j and 0.19 mu j. In the second scenario, we consider variation in traffic size. For 16 bytes traffic size, delay of extremely very high critical traffic is 5.8 ms and 14.5 ms for extremely low critical traffic. Similarly, extremely very high critical traffic consumes 0.035 mu j energy per bit, whereas extremely low critical traffic consumes 0.37 mu j. in the third scenario, the delay, data loss rate, average energy consumption and throughput for the proposed priority MAC are analyzed. Result demonstrates our proposed priority MAC protocol outperforms the state-of-the-art protocols.