Game Theoretic Analysis of a Byzantine Attacker in Vehicular Mix-Zones

Abstract

Vehicular ad hoc networks (VANETs) promises to enable a wide-range of safety and efficiency improvements to our roads. To secure VANETs, they are often designed with authenticated communications that allows for verification of the sender. In order to enable authenticated communications without sacrificing user privacy VANET designers often employ pseudonyms, temporary identifiers that are tied to a single user. In order to maximize location privacy, vehicles must temporally coordinate pseudonym changes using a mix-zone strategy. However, to be effective mix-zones either require vehicles to cooperate or have greedy motivation. Previously, game-theoretic analysis of greedy nodes have developed equilibrium strategies. However, this work did not consider malicious Byzantine attackers who only desire to minimize system-wide location privacy. In this work, we design two Byzantine attackers that target location privacy in VANETs. The first, which we call a naïve attacker, never cooperates. The second, which we call a stealthy attacker, attempts to minimize system wide location privacy while not being detected. We simulate both of these attackers and show that an attacker can reduce location privacy in a mix-zone by up to 12%.