A Key Management Scheme for Cluster Based Wireless Sensor Networks

Key management is a major challenge to achieve security in wireless sensor networks. In most of the schemes presented for key management in wireless sensor networks, it is assumed that the sensor nodes have the same capability. The recent research has shown that the survivability of the network can be improved if sensor nodes are grouped in clusters in which a powerful cluster head assigned. However, to gain advantages of clustering in order to find an efficient key management scheme needs more research. In this paper, we investigate the key management in cluster-based wireless sensor networks using both private and public key cryptography. Our goal is to introduce a platform in which public key cryptography is used to establish a secure link between sensor nodes and gateways. Instead of pre-loading a large number of keys into the sensor nodes, each node requests a session key from the gateway to establish a secure link with its neighbors after clustering phase. The security analysis and performance evaluation show that the proposed scheme has significant saving in storage space, transmission overhead, and perfect resilience against node capture.