PERT: a new power-efficient real-time packet delivery scheme for sensor networks

We present PERT, a power-efficient scheme to deliver real-time data packets in sensor networks. Time-sensitive sensor data is common in applications such as hazard monitoring systems, traffic control systems and battlefield command systems. Such data are associated with end-to-end deadlines, within which they must reach the base station. We make two contributions in this work. First, we propose a novel loadbalanced routing scheme that distributes data packets evenly among the nodes relaying data towards the base station, avoiding bottlenecks and increasing the likelihood that packets will meet their deadlines. Second, we propose a method of grouping smaller packets into larger ones by delaying data transmissions at the relaying nodes whenever slack times are positive. Our packet grouping scheme significantly reduces packet transmissions, reduces congestion, and saves power in the sensor network. We verify the effectiveness of our approach through extensive simulations of wireless network behavior using the ns-2 simulation package.