Monitoring Top-k Query inWireless Sensor Networks

Top-k monitoring is important to many wireless sensor applications. This paper exploits the semantics of top-k query and proposes a novel energy-efficient monitoring approach, called FILA. The basic idea is to install a filter at each sensor node to suppress unnecessary sensor updates. The correctness of the top-k result is ensured if all sensor nodes perform updates according to their filters. We show via simulation that FILA outperforms the existing TAGbased approach by an order of magnitude.