Efficient Revocation of Malicious Vehicles in VANETs

Intelligent Transport Systems (ITS) leverage cutting edge technology to enhance the reliability, protection and effectiveness of transportation. Dedicated Short Range Communication (DSRC) is the mean by which Vehicular Ad Hoc Networks (VANETs) provide connectivity among vehicles in form of vehicles to vehicle (V2V) and vehicle to roadside infrastructure (V2I). Maintaining safe connections in VANETs is a major issue due to malicious behavior of unlawful vehicles. Therefore, in order to protect VANETs, malicious vehicles should be revoked, for this purpose Certificate Revocation List (CRL) is distributed by the authorities among the VANETs users. However, due to the passage of time CRL size increased and becomes large, which produces delays in checking and verification of messages and results in disruption. Therefore, dissemination, updating, and searchable processes of traditional CRL techniques face latency and scalability problems. This paper aims to overcome these challenges by eliminating dependency on CRLs, introducing efficient revocation verification, and enabling a self-sufficient revocation mechanism. A novel ERMV approach is proposed, in which Bad-Hash is applied only to pseudonym certificates of revoked vehicles, which facilitates onboard, independent certificate status verification without the need to distribute, obtain or check CRLs. The proposed technique ensures rapid certificate status verification with minimal computational and communication overheads. The results show that the proposed technique can verify over 900 messages in a 300millisecond time frame, which illustrates that the proposed technique can work efficiently in sparse and dense scenarios with less computational and communication overheads.