Key management scheme based on nodes capture probability for wireless sensor networks

The security of wireless sensor network is becoming more and more important, in which key management is an important part to realize the security of the networks. In the hierarchical network, cluster heads play an important role in the network. Once being captured, they will expose more keys and information. Therefore, how to choose the cluster head should be considered seriously. However, the existing clustering algorithms only consider energy factor when selecting cluster heads. This paper proposes a model regarding probability of nodes being captured which not only considers the energy factors, but also considers the nodes capture probability when choosing cluster heads, so that nodes which hold smaller capture probability tend to be the cluster heads. On the basis of this model, an efficient key agreement scheme is proposed, which can use EBS (Exclusion Basis Systems) structure to update the group keys between clusters effectively. Simulation experiments show the proposed scheme has good connectivity and node capture resistance, and it can also save more storage cost.