A Lightweight Key Management Scheme for Wireless Sensor Networks

Key management is the core of security protocol for wireless sensor networks deployed in the hostile environment. Due to the strict resource constraints, traditional asymmetric key cryptosystems, such as public/private key based schemes, are infeasible for the wireless sensor networks. The existing random key based key pre-distribution schemes only provide some level of network resilience, 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. This paper presents an lightweight key management scheme for wireless sensor networks to address this problem. 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. Compared with existing key pre-distribution schemes, our scheme has better network resilience against node capture attack.