Revocation for Certificateless Authentication in VANETs

Abstract

This paper proposes a new way to deal with the problem of revocation of malicious users in vehicular ad-hoc networks. In particular, the proposal is designed to be used for identity-based authentication, which allows taking advantage of the efficiency and safety of certificateless authentication. In order to improve the performance of revocation lists, this paper proposes the use of a data structure based on authenticated dynamic hash k-ary trees and the frequency with which revoked pseudonyms are queried. Knowledge about query frequencies of revoked pseudonyms provides a more efficient access to the most popular revoked pseudonyms to the detriment of revoked pseudonyms that are the least queried. Accordingly, the proposal is especially useful in urban environments where there are vehicles that spend more time on the road than others.