An Improved Random Key Predistribution Scheme for Wireless Sensor Networks Using Deployment Knowledge

Key management is the basis of many security mechanisms and services in wireless sensor networks (WSN). Random key predistribution scheme is widely considered as the most practical for WSN. However, this scheme faces the challenge that it cannot achieve the ideal security connectivity and strong resilience against node capture simultaneously. To address this limitation, an improved random key predistribution scheme using deployment knowledge is proposed in this paper. Firstly, sensor nodes are divided into different groups according to their location expected. And the key pool is grouped into key pool subsets accordingly. To realize the communication between adjacent groups, the corresponding key pool subsets have a certain degree of overlapping. For all keys, there is no limitation on key reuse. Neighboring nodes sharing q common keys will establish secure link with high probability. Moreover, our scheme inherits the advantage of q-composite random key predistribution scheme that it can maintain security even if some nodes are captured. Theoretical analysis and simulation experiments show that the improved scheme performs well on network connectivity and resilience.