Intrusion Tolerant-based Lightweight CA Model for Wireless Mesh Networks

In a Wireless Mesh Network (WMN), we cannot assume the existence of a trusted certificate authority that is used in regular Public-Key Infrastructure (PKI). Hence a cooperative approach in which a cluster of some nodes can issue certificates to other nodes in a self-organizing manner is considered to be more suitable to the Ad-hoc nature of WMNs. In this paper, we propose a new trust establishment scheme providing an efficient and lightweight public key authentication without the presence of any trusted third party neither in bootstrapping network phase nor during network life time. Combined threshold mechanism and lightweight Certificate Authority idea, A lightweight and tolerate CA (LTCA) model has been put forwarded. LTCA is not only reformed to realize lightweight structure, but also equipped with intrusion tolerant ability which has been realized by dividing CA’s private key into n shares and distributing them into n servers. Simulation results show that the threshold mechanism does not significantly increase the computational cost of communication, but the security of LTCA’s private key is improved extremely.