Usage hybrid symmetric design of key pre-distribution for wireless sensor networks

Key distribution is one of the most challenging security issues in wireless sensor networks in which a list of keys, so-called key-ring, is pre-distributed to each sensor node before deployment. To achieve a high level of security, each pair of nodes must share a secret key in order to communicate with each other. Recently, many researchers have used combinatorial designs as key pre-distribution scheme in wireless sensor networks. In this paper, we present a hybrid approach based on the symmetric balanced incomplete block design to generate the key-rings. We propose a new approach for generating key-rings in the hybrid symmetric design that improves the connectivity of the network. Also, we compute the lower bound for radio range to have the secure connectivity in our proposed approach.