An Improved Pairwise Key Management Scheme for Wireless Sensor Networks

Key management in wireless sensor networks is a challenging problem because public key cryptosystems are unsuitable for using in resource constrained sensor nodes, and the nodes could by physically compromised by an adversary. For the existing key pre-distribution schemes, as the number of compromised nodes increasing, the fraction of affected pairwise keys will increase quickly. As a result, a small number of compromised nodes may affect a large fraction of pairwise. To address these weaknesses, in this paper we propose an improved key management scheme for wireless sensor networks. In the proposed scheme, we use hash function to alleviate the effect of compromised sensor nodes on the uncompromised sensor nodes and at the same time this method doesn´t affect the connectivity between neighboring sensor nodes. The analysis show that compared with existing schemes, the proposed scheme has better network resilience against node capture attack.