Trust based Approach for Improving Data Reliability in Industrial Sensor Networks

The resource constraints and unattended operation of wireless sensor networks make it difficult to protect nodes against capture and compromise. While cryptographic techniques provide some protection, they do not address the complementary problem of resilience to corrupted sensor data generated by failed or compromised sensors. Trusting data from unattended sensor nodes in critical applications can have disastrous consequences. We propose a behavior-based trust mechanism to address this problem in static sensor networks, in which the location of nodes is known. We take advantage of domain knowledge which includes: (i) physical constraints imposed by the local environment where sensors are located, (ii) expectations of the monitored physical phenomena; and (iii) sensor design and deployment characteristics. The system diagnoses and isolates faulty/malicious nodes even when readings of neighboring nodes are faulty. The goal of this system is to increase work effort and capabilities required by an attacker. The framework and related techniques of behavior-based trust are discussed in this paper.