An energy efficient collaborative framework for event notification in wireless sensor networks

Wireless sensor networks consist of large number of low power devices equipped with RF links for communication that have several military, civil and environmental monitoring applications. The energy constraints due to limited battery power present numerous design challenges. In this paper we propose an energy efficient, cluster based framework for collaboration among nodes in a region for reducing the redundancy in reporting events. Collaboration is done among the exposed nodes using a localized and deterministic schedule based on TDMA/FDMA MAC. A novel, three phase collaboration scheme is presented to exchange messages for determining the local maximum of the confidence measure in the two hop cluster neighborhood of the event. This local maximum generates the response for the event, thereby reducing the redundant reporting of the event. Through extensive simulations we have shown that there is a significant reduction in the overall network traffic thereby, saving energy at the nodes responsible for originating response traffic and also at nodes, which handle the route-through traffic.