Date Added: Jul 2011
Recent technological advancements and low price of deployment and maintenance of Wireless Sensor Networks (WSNs) allow their use in numerous applications in industry, research, and commerce, in order to gather environmental data in an unattended manner. Since, WSNs usually function in open environments, they may become a target of attacks or malicious activities aiming to gain access to data, manipulate aggregation result, or disrupt the network service. Therefore, intrusion detection becomes crucial for WSNs as a second line of defense. In order to detect "Smart" attacks of colluding devices, active monitoring of behaviors of neighboring nodes was proposed, but it is too energy expensive for resource-constrained WSN nodes, making an adaptive technique for activation of Intrusion Detection System (IDS) agents extremely important.