Lightweight Key Management in Wireless Sensor Networks by Leveraging Initial Trust

Abstract

This research is sponsored by DARPA under contract number F30602-02-C-0212. The views herein are those of the authors and do not necessarily reflect the views of the supporting agency. We present a novel approach for key management in wireless sensor networks. Using initial trust built from a small set of shared keys, low-cost protocols enable neighboring sensors to authenticate and establish secure local links. As the risk of sensor compromise increases with time, the keys are used only for a limited period right after deployment. Once secure local links are established, other security services such as group-key refresh can be provided. The protocols we present require little memory and processing power, and require a small number of shared keys independent of the network size. Moreover, these protocols do not depend on a trusted server or base station. To validate the applicability of our approach to ad hoc wireless sensor networks, we have implemented our protocols on the TinyOSbased