CSI: An Energy-Aware Cover-Sense-Inform Framework for k-Covered Wireless Sensor Networks

It is well known that sensor duty-cycling is an important mechanism that helps densely deployed wireless sensor networks (WSNs) save energy. On the other hand, geographic forwarding is an efficient scheme for WSNs as it requires maintaining only local topology information to forward data to their destination. Most of geographic forwarding protocols assume that all sensors are always on (or active) during forwarding. However, such an assumption is unrealistic for real-world applications where sensors are switched on or off (or inactive). In this paper, we describe our cover-sense-inform (CSI) framework for k-covered WSNs, where each point in a sensor field is covered by at least k active sensors. In CSI, k-coverage, sensor scheduling, and data forwarding are jointly considered. Based on our previous work on connected k-coverage [3], we propose the first design of geographic forwarding protocols for duty-cycled k-covered WSNs with and without data aggregation. Then, we evaluate the performance of our joint k-coverage and geographic forwarding protocols and compare them to CCP [37], a k-Coverage Configuration Protocol, with a geographic forwarding protocol on top of it, such as BVGF [36], which we have slightly updated in such a way that it considers energy for a fair comparison. Simulation results show that our joint protocols outperform CCP+BVGF.