摘要

Recently, there is an increasing interest in Security and Privacy issues in Vehicular ad hoc networks (or VANETs). However, the existing security solutions mainly focus on the preventive solutions while lack a comprehensive security analysis. The existing risk analysis solutions may not work well to evaluate the security threats in vehicular networks since they fail to consider the attack and defense costs and gains, and thus cannot appropriately model the mutual interaction between the attacker and defender. In this study, we consider both of the rational attacker and defender who decide whether to launch an attack or adopt a countermeasure based on its adversary's strategy to maximize its own attack and defense benefits. To achieve this goal, we firstly adopt the attack-defense tree to model the attacker's potential attack strategies and the defender's corresponding countermeasures. To take the attack and defense costs into consideration, we introduce Return On Attack and Return on Investment to represent the potential gain from launching an attack or adopting a countermeasure in vehicular networks. We further investigate the potential strategies of the defender and the attacker by modeling it as an attack-defense game. We then give a detailed analysis on its Nash Equilibrium. The rationality of the proposed game-theoretical model is well illustrated and demonstrated by extensive analysis in a detailed case study.