On the Performance of a Distributed Key Management Scheme in Heterogeneous Wireless Sensor Networks

Distributed key management is a major challenge in the design and deployment of secure wireless sensor networks (WSNs). In most existing distributed key management schemes, a common assumption is that all sensor nodes have the same capability. However, recent studies have demonstrated that heterogeneities of the sensor nodes, in particular the heterogeneities of energy capacity and transmission capability, can significantly improve the connectivity and lifetime of the WSNs. Consequently, it is important to design key management schemes for heterogeneous WSN (HWSN). In this paper, we provide a distributed key management scheme for HWSNs. The main contribution of this paper is to develop analytical models for evaluating the performance of the proposed scheme in terms of connectivity, reliability, and resilience. Extensive simulation results show that, with a small number of heterogeneous nodes, the WSN can achieve higher key connectivity, better reliability, and higher resilience. The results also show that our analytical models can accurately predict the performance under a variety of conditions