An efficient successive authentication scheme for vehicular ad-hoc networks

VANET (Vehicular Ad-hoc NETwork) is a network architecture designed to provide road safety, improve transport efficiency, and reduce traffic congestion by combining vehicles with high mobility and fixed road-side units with or without Vehicular Cloud. Connected vehicles aided with sensors need to be authenticated before transmitting message. Two major problems in existing state-of-the-art schemes which are redundant authentication of vehicles with each RSUs it passes through and authenticating each message by trusted authority with large cryptographic overheads. In this paper we proposed an authentication scheme which exploits a very new technique of successive message passing among different RSUs (Road-side Units) to verify vehicles which are already authenticated. In our scheme, RSUs share authentication related information of vehicles with the help of newly proposed RSUs detection algorithm. In addition to that, messages from vehicles are verified with assistance from RSUs using symmetric key based Hashed Message Authentication Code (HMAC) signatures. This results in remarkably reduced cryptographic overheads and communication delay occurred during authentication of vehicles and messages in VANETs. Extensive performance evaluations and comparison with state-of-the-art schemes will show how our scheme provides exceptionally improved performance for VANETs.