A game theoretic analysis of delay attacks against time synchronization protocols

Time synchronization protocols have become very common in packet networks, and are consequently exposed to various security attacks. One of the most effective attacks against synchronization protocols is the delay attack, in which a man-in-the-middle attacker selectively delays the time protocol packets. This attack is exceptionally effective, as it cannot be prevented by conventional security measures such as authentication or encryption. In this paper we introduce a new approach to analyzing the delay attack, using a game theoretic model. We analyze the possible strategies of the attacker and attackee, and introduce a novel strategy for mitigating delay attacks using multiple paths between the master and slave clocks. We also discuss the Nash equilibria in our model and their connection to the possible outcomes of real-life attacks.