A Polynomial Based Key Establishment Scheme for Heterogeneous Sensor Networks

Recently, many researches have focused on a multi-tiered architecture for sensor networks. The advantages of such an architecture are better scalability, energy efficiency and security. Unfortunately, the homogeneous sensor networks lack these advantages. Thus, we use this multi-tiered architecture in this paper. Wireless sensor networks are usually deployed in hostile or dangerous environments, so the communications among nodes have to be encrypted. Furthermore, adversaries may capture or compromise nodes in the sensor networks. The keying material of the compromised nodes may be known by adversaries. Thus, the consequence of node capture attack has to be minimized. In this paper, we employ a polynomial to establish a pairwise key between any two nodes in a cluster. In addition, each sensor can also establish pairwise keys, in all probability, with its neighbors deployed in other clusters. The security analysis shows that our scheme provides better security, compared with the existing key establishment scheme.