An Improved Intrusion Detection Scheme Based on Weighted Trust Evaluation for Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are widely applied to monitor environments such as military surveillance and reconnaissance. However, individual sensor nodes are vulnerable to some types of attacks because they are usually deployed in open and unprotected environments. Once sensor nodes are compromised, malicious nodes can send erroneous data to the base station, and possibly mislead monitoring results and influence the whole networks' effectiveness. We need to find new mechanisms to protect the wireless networks from attacks. In this paper we develop a scheme for malicious node detection based on weighted-trust evaluation. A weight value is assigned to each sensor node initially. It updates every cycle if the node sends different report from the others. A malicious node will be detected when its weight value is lower than a threshold value. The simulation results show that our approach is more effective in detecting malicious nodes with lower misdetection ratio compared with existing schemes.