Date Added: Jun 2009
Geocast sends packets to all sensor nodes within a specified geographical region in order to gather data from sensor nodes in that region and is an important mechanism in sensor networks. In this paper, the authors first introduce an energy-efficient geocast protocol. The proposed protocol builds multicast tree connecting geocast nodes using an energy efficient broadcasting technique without making any restrictions on the shape of the geocast region. The proposed protocol reduces the energy consumption during the phase of sending commands to the sensor nodes in a geocast region. It also facilitates in-network data aggregation and, therefore, helps save energy during the data reporting phase.