Abstract
In this paper, the authors propose a dynamic Public Key Infrastructure (PKI) for vehicular ad hoc networks to distribute the role of the central certification authority (CA) among a set of dynamically elected CAs. The election process is based on a clustering algorithm relying on trust levels and relative mobility. Furthermore, the authors have adapted the Dynamic Demilitarized Zones to protect the elected CAs from malicious nodes and enable them to act as registration authorities (RA). Extensive simulations are conducted to evaluate the performance of the clustering algorithm and investigate the impact of the vehicle speed, the vehicle average arrival rate, and the percentage of confident vehicles on the stability and efficiency of the security infrastructure. The authors demonstrate the percentage of confident nodes has a little impact on these performance metrics and that the minimum number of CAs to cover the entire platoon.