A secure mutual trust scheme for wireless sensor networks

In this paper, we propose a secure mutual trust scheme based on the concept of chameleon hash function, for wireless sensor networks (WSNs). In the proposed scheme, the base station (BS), holding two common secrets, issues an identity to every deployed sensor node. An identity contains a public data and a private key. The public data is used to present a node, and the private key is used to make mutual trust keys with other node's public data. A public data can be used in verifying the legitimacy of the node. The mutual trust key is the evidence that a node owns the related public data. At any time, or after finding malicious nodes or deploying new nodes, BS will broadcast new group key to all sensor nodes by multiple hopping. Following the group key broadcasting and rebroadcasting, the still-legal nodes can set new information in their public data, private key, hop counters, public parameters, and neighbor nodes set, which contains the public data and hop counter of its neighboring nodes. Based on the new information, a sensor node can make the mutual trust keys with its neighboring nodes to do message authentication and secure communicating, or to set up a secure path to forward the sensed information to BS by multiple relaying. The security analysis shows that the proposed scheme can revoke the right of malicious sensor nodes, deploy new sensor nodes, and work well under malicious attacking. As the result of performance comparison, the proposed secure scheme is superior to the related works.