Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> In this paper, we propose a medium access control (MAC) protocol to support the multi-channel operation for dedicated short range communication (DSRC). In particular, we focus on the challenge of providing potentially high-bandwidth for non-safety applications provided by roadside infrastructure, without compromising safety communication occurring in a separate channel. In our architecture, when a vehicle approaches a DSRC service hot-spot, it switches from the ad-hoc mode to the coordinated mode (and switches back to ad-hoc as it leaves the hotspot's range). This coordinated mode is a variant of IEEE 802.11 PCF, modified for multi-channel operation. The coordinated mode maximizes utilization of the DSRC "service channels" in the DSRC hot-spots while allowing safety-message broadcasts to be received with high probability in a distinct "safety channel". When a vehicle is not within the range of a DSRC hot-spot, the vehicle can use any of the previously-proposed ad-hoc protocols. Our approach can use any of these ad-hoc protocols for its ad-hoc mode. The MAC protocol is simulated with realistic mobility trace, and verified that it meets our safety and service objectives. <s> BIB001 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <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> BIB002 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <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> BIB003 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> We propose a medium access control protocol design for a vehicle to send safety messages to other vehicles. We develop a Quality-of-Service (QoS) model for safety messages that are consistent with the active vehicle safety systems literature. Each message has a range and useful lifetime. The QoS target has each message received with high probability within its specified lifetime by each vehicle within its specified range. The protocol design is based on rapidly rebroadcasting each message multiple times within its lifetime in combination with the 802.11 Distributed Coordination Function. This makes the design compatible with emerging standards for Dedicated Short-Range Communication. Six different design variations are proposed. We derive equations and develop a simulation tool to assess the performance of the designs. Using these, we identify the best and most easily implemented designs. Design performance depends on the number of rebroadcasts, power, modulation, coding, and vehicular traffic volumes. We show that under certain assumptions on the loss probability tolerated by safety applications, the design is able to transport safety messages in vehicular ad hoc networks <s> BIB004 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular networks have attracted extensive attentions in recent years for their promises in improving safety and enabling other value-added services. Security and privacy are two integrated issues in the deployment of vehicular networks. Privacy-preserving authentication is a key technique in addressing these two issues. We propose a random keyset based authentication protocol that preserves user privacy under the zero-trust policy, in which no central authority is trusted with the user privacy. We show that the protocol can efficiently authenticate users without compromising their privacy with theoretical analysis. Malicious user identification and key revocation are also described <s> BIB005 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Privacy and security should be paid much more attention in secure vehicular ad hoc networks (VANETs). However, as far as we know, few researches on secure VANET protocols have addressed both the privacy issues and authenticated key establishment. Therefore, in this work, a lightweight authenticated key establishment scheme with privacy preservation to secure the communications between mobile vehicles and roadside infrastructure in a VANET is proposed, which is called SECSPP. Our proposed scheme not only accomplishes vehicle-to-vehicle and vehicle-to-roadside infrastructure authentication and key establishment for communication between members, but also integrates blind signature techniques into the scheme in allowing mobile vehicles to anonymously interact with the services of roadside infrastructure. We also show that our scheme is efficient in its implementation on mobile vehicles in comparison with other related proposals. <s> BIB006 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular communication networking is a promising approach to facilitating road safety, traffic management, and infotainment dissemination for drivers and passengers. One of the ultimate goals in the design of such networking is to resist various malicious abuses and security attacks. In this article we first review the current standardization process, which covers the methods of providing security services and preserving driver privacy for wireless access in vehicular environments (WAVE) applications. We then address two fundamental issues, certificate revocation and conditional privacy preservation, for making the standards practical. In addition, a suite of novel security mechanisms are introduced for achieving secure certificate revocation and conditional privacy preservation, which are considered among the most challenging design objectives in vehicular ad hoc networks. <s> BIB007 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> In 1998, Blaze, Bleumer, and Strauss suggested a cryptographic primitive named proxy re-signatures where a proxy turns a signature computed under Alice's secret key into one from Bob on the same message. The semi-trusted proxy does not learn either party's signing key and cannot sign arbitrary messages on behalf of Alice or Bob. At CCS 2005, Ateniese and Hohenberger revisited the primitive by providing appropriate security definitions and efficient constructions in the random oracle model. Nonetheless, they left open the problem of designing a multi-use unidirectional scheme where the proxy is able to translate in only one direction and signatures can be re-translated several times. ::: This paper solves this problem, suggested for the first time 10 years ago, and shows the first multi-hop unidirectional proxy re-signature schemes. We describe a random-oracle-using system that is secure in the Ateniese-Hohenberger model. The same technique also yields a similar construction in the standard model (i.e. without relying on random oracles). Both schemes are efficient and require newly defined -- but falsifiable -- Diffie-Hellman-like assumptions in bilinear groups. <s> BIB008 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> VANETs have the potential to dramatically increase road safety by giving drivers more time to react adequately to dangerous situations. To prevent abuse of VANETs, a security infrastructure is needed that ensures security requirements like message integrity, confidentiality, and availability. After giving more details on the requirements we propose a security infrastructure that uses asymmetric as well as symmetric cryptography and tamper resistant hardware. While fulfilling the requirements, our proposal is especially designed to protect privacy of the VANET users and proves to be very efficient in terms of computational needs and bandwidth overhead. <s> BIB009 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular networks are very likely to become the most pervasive and applicable of mobile ad hoc networks in this decade. Vehicular Ad hoc NETwork (VANET) has become a hot emerging research subject, but few academic publications describing its security infrastructure. In this paper, we review the secure infrastructure of VANET, some potential applications and interesting security challenges. To cope with these security challenges, we propose a novel secure scheme for vehicular communication on VANETs. The proposed scheme not only protects the privacy but also maintains the liability in the secure communications by using session keys. We also analyze the robustness of the proposed scheme. <s> BIB010 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular ad hoc networks (VANETs) allow vehicle-to-vehicle communication and, in particular, vehicle-generated announcements. Provided that the trustworthiness of such announcements can be guaranteed, they can greatly increase the safety of driving. A new system for vehicle-generated announcements is presented that is secure against external and internal attackers attempting to send fake messages. Internal attacks are thwarted by using an endorsement mechanism based on threshold signatures. Our system outperforms previous proposals in message length and computational cost. Three different privacy-preserving variants of the system are also described to ensure that vehicles volunteering to generate and/or endorse trustworthy announcements do not have to sacrifice their privacy. <s> BIB011 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Advances in wireless communications allow setting up communication links between vehicles for the exchange of information between them. Such vehicular ad hoc networks (VANETs) are important to enhance traffic safety since critical environmental conditions, such as road or traffic conditions, can be rapidly exchanged between vehicles in VANETs. However, to be useful for the driver, the information must be reliable, i.e., with great probability, the received information indeed reflects the actual situation. One approach to this is to regard information as reliable if it is confirmed by various sources. To achieve this, messages received must be distinguishable. This may become a threat against the privacy of drivers since by observing messages, vehicles may be traced. In this paper, we address the mentioned problems. We base the reliability of information on the number of different sources that confirmed specific information, and that number must be greater than a given threshold. We address the nontraceability by letting vehicles change their identity frequently. Our approach scales with respect to storage on the vehicle, as well as management of identities at a certification authority. <s> BIB012 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> In this paper, we propose an efficient distributed-certificate-service (DCS) scheme for vehicular networks. The proposed scheme offers flexible interoperability for certificate service in heterogeneous administrative authorities and an efficient way for any onboard units (OBUs) to update its certificate from the available infrastructure roadside units (RSUs) in a timely manner. In addition, the DCS scheme introduces an aggregate batch-verification technique for authenticating certificate-based signatures, which significantly decreases the verification overhead. Security analysis and performance evaluation demonstrate that the DCS scheme can reduce the complexity of certificate management and achieve excellent security and efficiency for vehicular communications. <s> BIB013 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular ad hoc networks (VANETs) are being designed to improve traffic safety and efficiency. To meet this goal, the messages disseminated in VANETs must be trustworthy. We propose a privacy-preserving system that guarantees message trustworthiness in vehicle-to-vehicle (V2V) communications. Vehicle privacy is provided as long as a vehicle does not attempt to endorse the same message more than once. In spite of a message having been validly endorsed, if it is later found to be false, the system offers the possibility of a posteriori tracing the message generator and its endorsers. Our proposal demonstrates a number of distinctive features. The system is equipped with both a priori and a posteriori countermeasures. The threshold used for a priori endorsement can adaptively change according to the message urgency and traffic context, rather than being preset in the system design stage as in existing schemes. The verification of authenticated V2V messages is accelerated by batch message-processing techniques. Simulation results illustrate that the system maintains its performance under various traffic conditions. <s> BIB014 </s> Anonymous Authentication Protocols for Vehicular Ad Hoc Networks: An Overview <s>  <s> Vehicular ad hoc networks (VANETs) allow wireless communications between vehicles without the aid of a central server. Reliable exchanges of information about road and traffic conditions allow a safer and more comfortable travelling environment. However, such profusion of information may allow unscrupulous parties to violate user privacy. On the other hand, a degree of auditability is desired for law enforcement and maintenance purposes. In this paper we propose a Threshold Anonymous Announcement service using direct anonymous attestation and one-time anonymous authentication to simultaneously achieve the seemingly contradictory goals of reliability, privacy and auditability. <s> BIB015
security and privacy preservation for mobile vehicles  ; BIB015 ; BIB011 Hubaux et al. (2004) ; Kamat et al. (2006) ; BIB012 ; BIB006 ; BIB003 BIB007 BIB008 ; ; BIB001 ; BIB009 ; BIB002  ; 2010a; BIB008 ; BIB013 ; BIB010 ; BIB014 ; BIB004 ; BIB005  ; Xiong et al. (2010a; BIB008 ; BIB007 BIB008 . Obviously, any malicious behaviors of user, such as injecting beacons with false information, modifying and replaying the previously disseminated messages, could be fatal to the other users. Thus, identifying the message issuer is mandatory to reduce the risk of such attacks. Meanwhile, in order to protect the user-related private information, such as the driver's name, the license plate, speed, position, and travelling routes along with their relationship, authentication in VANETs should be privacy-preserving. It is natural to observe that achieving privacy and liability simultaneously is conflicting goal. On one aspect, a well-meaning OBU is willing to offer as much local information as possible to RSUs and other OBUs to create a safer driving environment so long as its locations cannot be tracked. And on the other, a misbehaving OBU may abuse the privacy protection mechanism to avoid legal responsibility when it involved in a dispute involving safety messages 2 attempts. Therefore, the conditional privacy-preserving authentication should be fulfilled in VANETs where a trusted authority can reveal the real identity of targeted OBU in case of a traffic event dispute, even though the OBU itself is not traceable by the public. This chapter surveys the literature on privacy issues in VANETs from different perspectives, and thus provides researchers with a better understanding of this primitive. This chapter does not propose or advocate any specific anonymous authentication mechanisms. Even though some sections might point out vulnerabilities in certain classes of authentication protocols, our purpose is not to criticize, but to draw attention to these problems so that they might be solved. The remainder of this chapter is organized as follows. Section 2 presents attack model, security requirements and related VANETs network architecture. All previous privacy-preserving protocols for VANETs are classified in Section 3, together with the basic cryptographic primitives. An example of Ring-signature based anonymous authentication protocol based on bilinear pairing are given in Section 4. Section 5 discusses how to use the taxonomies. Section 6 concludes the paper by stating some possible future research directions.