Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s> Attack model <s> Vehicular networks are likely to become the most relevant form of mobile ad hoc networks. In this paper, we address the security of these networks. We provide a detailed threat analysis and devise an appropriate security architecture. We also describe some major design decisions still to be made, which in some cases have more than mere technical implications. We provide a set of security protocols, we show that they protect privacy and we analyze their robustness, and we carry out a quantitative assessment of the proposed solution. <s> BIB001 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s> Attack model <s> In this paper, we first identify some unique design requirements in the aspects of security and privacy preservation for communications between different communication devices in vehicular ad hoc networks. We then propose a secure and privacy-preserving protocol based on group signature and identity (ID)-based signature techniques. We demonstrate that the proposed protocol cannot only guarantee the requirements of security and privacy but can also provide the desired traceability of each vehicle in the case where the ID of the message sender has to be revealed by the authority for any dispute event. Extensive simulation is conducted to verify the efficiency, effectiveness, and applicability of the proposed protocol in various application scenarios under different road systems. <s> BIB002
According to  ; BIB002 ; BIB001  ; , several possible security attacks in VANETs have been defined and listed as follows: • Fake information attack: The adversary may diffuse bogus messages to affect the behavior of others. For instance, in order to divert traffic from a given road, one may send a fake traffic jam message to the others. • Message replay attack: The adversary replays the valid messages sent by a legitimate user some time before in order to disturb the traffic. • Message modification attack: A message is altered during or after transmission. The adversary may wish to change the source or content of the message in terms of the position and/or time information that had been sent and saved in its device notably in the case of an accident. • Impersonation attack: The adversary may pretend to be another vehicle or even an RSU by using false identities to fool the others. • RSU preemption/replication attack: An RSU may be compromised such that the adversary can relocate the compromised RSU to launch any malicious attack, such as broadcasting fake traffic information. Moreover, the adversary may illegally interrupt and manipulate traffic lights which is controlled by the corrupted RSU to get a better traffic condition • Denial of service (DoS) attack: The adversary injects irrelevant jamming and aggressive dummy messages to take up the channels and consume the computational resources of the other nodes, such as RF interference or jamming or layer 2 packet flooding. • Movement tracking: Since wireless communication is on an openly shared medium, an adversary can easily eavesdrop on any traffic. After the adversary intercepts a significant amount of messages in a certain region, the adversary may trace a vehicle in terms of its physical position and moving patterns simply through information analysis. Assuming that the attacker does not make use of cameras, physical pursuit, or onboard tracking devices to reveal the identity of his target; otherwise, the tracking problem becomes simpler but also more expensive and limited to few specific targets.