CERIAS Tech Report 2015-13 Distance-based Trustworthiness Assessment for Sensors in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) have been substituting for human senses to make human lives better by monitoring the environ­ ment and providing intelligence. Collected sensor data are used to make decisions as a human does. Therefore, providing trustworthy sensor data is crucial to make correct decisions. However, faulty sensors can give in­ correct information. In addition, since sensors are usually deployed in unattended areas and can be compromised, cryptographic approaches are insufficient. To address this problem, we propose a distance-based trustworthiness assessment scheme. In our scheme, a centralized trust assessment module outputs an absolute trust score of each sensed value and the trust score of each sensor. The trust scores of sensed values are calculated based on the differences of sensed values provided by a sensor and its neighbors and the physical distances from the neighbors. Our simulation results show that our scheme outputs practical and accurate trust scores in a realistic environment where the sensed values of interest gradually change over the monitored areas.