MOTE: Efficient monitoring of top-k set in sensor networks

Top-k monitoring is a noteworthy query that recently has been put into practice in wireless sensor networks (WSN). In top-k monitoring (i.e., an instance of continuous distributed monitoring), base station or coordinator continuously monitors k sensors with the highest (or lowest) values. Since the goal in such applications is to perform monitoring task while incurring minimum communication (data traffic) overhead, local constraints should be set at remote sites to filter unnecessary updates. Thereby, the novelty of this paper lies on the investigation of a method called MOTE where model-based optimization technique is utilized to set filters at remote sensors. In the proposed technique, the problem of optimal filter setting for maintaining top-k set is formulated as a variant of set cover which is an np-hard problem with well studied approximation methods. Simulation results demonstrate the validity of the proposed MOTE algorithm in improving the performance compared to other filter setting methods.