urgMAC: A New Traffic and QoS-aware Cross-Layer MAC protocol for Wireless Multimedia Sensor Networks

Abstract

Wireless Multimedia Sensor Networks (WMSNs) transmit heterogeneous data having different quality of service and urgency constraints. WMSNs focus on offering QoS for multimedia transmission while Wireless Sensor Networks focus on minimizing energy consumption. To overcome urgency challenges, a new traffic and QoS-aware cross-layer MAC protocol for WMSNs namely urgMAC is proposed in this paper. The urgMAC aims to provide continuous QoS support with video quality tradeoff at the application layer dynamically for applications such as habitat monitoring, military border surveillance and border monitoring containing specific urgency challenges. To this end, the urgMAC includes new mechanisms called Two Tiered Service Differentiation Mechanism, Adaptive Data Rate Adjustment Mechanism, Urgency-based Contention Window Size Adaptation, Traffic Type Adaptive Duty Cycle and Multimedia Message Passing. The urgMAC has been modeled and simulated by Riverbed Modeling and Simulation Software. In addition, the urgMAC is compared with the recent protocols in the literature, and it achieves better results in terms of end-to-end delay and channel utilization.