Abstract
Some applications in wireless sensor networks (WSNs) only need to record information of a target entering or leaving some specific regions of WSNs perimeter One important issue in this context is to detect the perimeter of the deployed network to ensure that the sensor nodes cover the target area In this paper we propose two distributed algorithms to elect the perimeter nodes of query regions in a WSN We consider the most general ease, where every sensor hat, a different sensing radius We provide performance metrics to analyze the performance of our approach and show by simulation that the proposed algorithms give good performance