Efficient and Scalable Certificate Revocation List Distribution in Hierarchical VANETs

Vehicular ad-hoc networks (VANETs) have become an emerging technology that can fulfill the demand of evolving connected vehicles and growing need for Intelligent Transportation System (ITS). Certificates are used to secure vehicular communication but the certificates of vehicles need to be revoked if any vehicles are found as misbehaving nodes. In VANETs, certificate revocation list (CRL) must be quickly distributed to all vehicular nodes to prevent from undesirable communication with the malicious nodes. However, due to growing number of the certificates, the size of CRL continuously increases, and as a result, it becomes difficult to manage and distribute the CRL in the vehicular networks. In this paper, we present an efficient and scalable scheme to distribute certificate revocation list in the hierarchical architecture of VANETs. Our analysis shows that proposed scheme can distribute certificate revocation list promptly throughout the networks while maintaining low CRL size.