Utility-Based Data-Gathering in Wireless Sensor Networks with Unstable Links

Abstract. Traditional utility-based data-gathering models consider the maximization of the gathered information and the minimization of energy consumption in WSNs with reliable channels. In this paper, we extend the model to include retransmissions caused by link failure to improve network utility. The challenge lies in balancing two competing factors: energy loss (and hence utility) through retransmissions and increased reliability (and hence utility) through retransmissions. We adopt a utility-based metric proposed in our previous work [9] and show the NP-hardness of the problem, regardless of the number of source sensors. We design several approximation heuristics for either case and compare their performances through simulation. We also study the impact of retransmissions on the maximization of network utility. Extensive simulations through a customized simulator are conducted to verify our results. Keywords: Data-gathering, heuristic solution, network utility, routing, stability, wireless sensor networks (WSNs).