Performance Evaluation of Network Coding and Packet Skipping in IEEE 802.15.4-Based Real-Time Wireless Sensor Networks

In a number of application domains, the volatility of the monitored environment where Wireless Sensor Networks (WSNs) operate engenders timing constraints on the generation, processing, and communication of sensory data. In this paper, we primarily focus on the use of an information theoretic approach, namely network coding, to improve the on-time delivery of messages in IEEE 802.15.4-compliant networks. We further study the real-time gain that packet skipping can provide on its own and in combination with network coding. Subsequently, we investigate the potential benefits of introducing deadline-awareness into the coding mechanism through the use of an Earliest Deadline First (EDF) based scheduling policy. Simulation results show that network coding and packet skipping are by themselves effective techniques to increase on-time goodput, with additional gain obtained when the two techniques are used concurrently. Our results further provide insight into the performance of deadline-aware scheduling in a network coding environment.