Date Added: Feb 2010
Wireless sensor networks are being increasingly used to due to its vast spectrum of applications including surveillance, security, healthcare, asset tracking and environmental monitoring. Such a network consists of large numbers of nodes which are placed in a region in order to gather and transmit information about activities in that region. Each node is a low power device consisting of sensors and communication units with limited processing power. In general, since sensor networks deployment and replacement of nodes in a sensor network is an expensive process, it is of great interest to conserve energy resources in the network and extend the lifetime of the network.