A Key Pre-distribution Scheme based on Sub-regions for Multi-Hop Wireless Sensor Networks

The key pre-distribution schemes in wireless sensor networks (WSNs) have attracted researchers’ attentions recently in some applications. These researches of key pre-distribution focus on the balance among security, energy overhead and network resilience, because of the low computing ability, small storage and limited energy of nodes in WSNs. In this paper, a key pre-distribution scheme based on sub-regions is proposed for multi-hop wireless sensor networks. The significant contribution of this scheme is that both the least number of polynomials stored in one sensor node and the least number of nodes storing the same polynomial can be determined such that any two neighbor nodes can communicate securely. The sub-regions are formed by diffusing hop-by-hop without any node’s location information, and every node has at least one common polynomial with its neighbors to generate the session key between them. Even if k (k < t/2 + 1) nodes are compromised, the network, whose keys are produced by t-degree symmetric bivariate polynomials, still keeps secure. Moreover, the scheme balances the contradictory relationship among encryption techniques, energy overhead and network resilience. The theoretical analysis and simulation results show the scheme outperforms the poly&&q-composite scheme and sequence-based key management scheme in terms of energy overhead and network resilience.