A novel dynamic key management scheme for wireless sensor networks

The key management of wireless sensor networks is one of the most important research topics for the secure communications. In light of the unique characteristics in Wireless sensor network such as large scale of deployment, mobility of nodes, node failures, communication failures and dynamic network topology, many dynamic key management schemes, such as SHELL and LOCK, have been proposed to guarantee the security of key management. But they could not completely address the collusion problem of key management in wireless sensor networks. In this paper, we devote to solving this problem and present a novel scheme for secure communications in wireless sensor networks. Our scheme follows the architecture of the three layers in LOCK. Concretely, we employ the ciphertext-policy attribute based encryption to refresh the group key in the upper layer and use EBS in the lower layer. Compared with related ones, our scheme can avoid the collusion attacks. Moreover, in the aspect of communication overhead, the number of messages for rekeying in our scheme can be largely reduced.