On the Resilience to Node Capture Attacks of Secure Wireless Sensor Networks

Despite much research on probabilistic key predistribution schemes for wireless sensor networks over the past decade, few formal analyses exist that define schemes' resilience to node-capture attacks precisely and under realistic conditions. In this paper, we analyze the resilience of the q-composite key predistribution scheme, which mitigates the node capture vulnerability of the Eschenauer-Gligor scheme in the neighbor discovery phase. We also show that this scheme can be easily enhanced to achieve the same "perfect resilience" property as in the random pairwise key pre-distribution for attacks launched after neighbor discovery. Despite considerable attention to this scheme, much prior work explicitly or implicitly uses an incorrect computation for the probability of link compromise under node-capture attacks. Based on our rigorous results, we provide guidelines on the design of secure sensor networks for resilience against node capture.