Logical ring based key management for clustered sensor networks with changing cluster head

Cluster based organization is widely used to achieve energy efficiency in Wireless Sensor Networks (WSN). In order to achieve confidentiality of the sensed data it is necessary to have secret key shared between a node and its cluster head. Key management is challenging as the cluster head changes in every round in cluster based organization. In this paper we propose two schemes for key management in clustered sensor networks with changing cluster head. In Simple Secure Logical Ring (SSLR) scheme communication and computation cost incurred for key establishment is constant. Whereas in Burmester Desmedt Logical Ring (BDLR) scheme key establishment is achieved by performing (n + 1) multiplications and (n+ 5) communications, where n is the number of nodes in the cluster. Simulation results show that node compromise in the proposed schemes is handled efficiently.