Research On Authentication Techniques With Privacy Preserving In Vehicular Ad-hoc Networks

With the popularity of cars and the development of network technology, naturally the ideaof combining these two techniques is genertaed, therefore, the concept of Vehicular Ad hocNetworks(VANETs) is put forward.Because of VANETs’s broad application prospects, VANETs has become a research focusin both industry and academica world. The security and privacy issue in VANETs isparticularly crucial because if they are not solved, VANETs can not be applicated in a largescale in our daily life. In this paper, we focus on one of the security and privacy issues inVANETs----authentication techniques with privacy preservation. In general, authenticationcan be broken down to two classes: data-origin authentication (or message authentication) andentity authentication (or identification). In VANETs both of them generally can not protect theprivacy (such as true identity or location information) of the entities involved in the process ofauthentication. There are two classes of protocols aiming at the privacy preserving of theauthentication in VANETs. One is the group signature technique based protocol, and the otheris the huge anonymous pseudonyms based protocol. Our two protocols are both belonged to thesecond class.In this paper, the main research results are as follows:1. In the specific application background, an improved electronic toll collection schemewith anonymous authentication in VANETs is proposed. This scheme can protect the privacy,such as the identity and the location (path) of the vehicles in VANETs. The improved scheme ismore suitable for China’s tolling by distance mode, provides stronger privacy of the vehicle. Weadd an anonymous authentication protocol in the driving phase to repair a big security flaw inthe original scheme. By using this anonymous authentication protocol, we drop the spot checkenforcement measure in the original scheme to improve the efficiency in the reconciliationphase; we explain how to track the illegal vehicles in our improved scheme. Finally, wedemonstrate the higher security and higher efficiency gained by the improved scheme throughextensive analysis.2. We give an improved authentication scheme in VANETs with privacy presearvingbased on Huang et al.’s scheme in [65]. Our improved scheme uses the pseudonyms techniqueto protect the privacy of the vehicle. With the help of RSUs, vehicles generate pseudonyms foranonymous communication. By using the BLS short signature scheme based on elliptic curvecryptography and identity-based encryption technology, the security of the scheme isguaranteed. Our improved scheme introduces the authentication function to repaire some flawsof the oringinal scheme. We add batch verification in the pseudonyms generation phase to reduce the burden of RSUs and this will improve the efficiency of the entire system. Ourscheme is more practical, especially when the RSUs’ density is very low.