Performance Evaluation of the IEEE 802.15.4 CSMA-CA Protocol with QoS Differentiation

In this paper, we investigate the performance of quality of service (QoS) differentiation schemes for the IEEE 802.15.4 carrier sense multiple access with collision avoidance (CSMA-CA) protocol. The differentiation schemes provide QoS prioritization in terms of data latency and transmission reliability in wireless sensor networks. In the latency differentiation scheme (LDS), we use different strategies to adjust backoff window sizes to prioritize different types of nodes. In the reliability differentiation scheme (RDS), more transmission attempts are given to the nodes having stricter reliability requirement when busy channels and collisions are detected. Simulation results show that the prioritized nodes can achieve significantly less latency (up to ten times less) and higher packet success rate (up to twice more) than the normal nodes.