Abstract: Wireless sensor network consists of a huge number of tiny electromechanical sensor devices that are capable of sensing, computing and communicating. These electromechanical sensor devices can be made use for gathering sensory information, like measurement of temperature from an extensive geographical area. Many features of the wireless sensor networks have given rise to challenging problems. Sensor nodes are deployed in open hostile environment in WSN applications. An adversary can easily compromise sensor nodes due to their unattended nature. Adversaries can inject false data reports into the WSN through compromised nodes. The false data reports lead the en-route nodes and the base station to make false decision. False decision depletes the energy of en-route nodes and the base station.

Keywords: WSN, sensor nodes, aggregator.