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Secure Clustering Scheme Based Keys Management in VANETs

We propose an efficient dynamic architecture of the Public Key infrastructure (PKI) for vehicular ad hoc networks (VANETs) based on a trust model and a novel distributed clustering algorithm. Furthermore, we introduce the notion of a VANET Dynamic Demilitarized Zone (VDDZ), composed of the set of confident vehicles located within the immediate neighborhood of each clusterhead (CH) to assume the Registration Authorities (RA). The VDDZ aims to secure the elected CAs by shielding them from unknown or malicious vehicles. A host of simulations using urban and highway scenarios are conducted to investigate the effects of the transmission range, the speed of vehicles and the number of confident vehicles in the network on the security level, the stability and the efficiency of our proposed architecture. In particular, the results show a strong dependency of the security and the stability on the assumed percentage of trust nodes and the mobility models.