Vehicular ad hoc networks (VANETs) are becoming the most promising research topic in intelligent transportation systems, because they provide information to deliver comfort and safety to both drivers and passengers. However, unique characteristics of VANETs make security, privacy, and trust management challenging issues in VANETs’ design. This survey article starts with the necessary background of VANETs, followed by a brief treatment of main security services, which have been well studied in other fields. We then focus on an in-depth review of anonymous authentication schemes implemented by five pseudonymity mechanisms. Because of the predictable dynamics of vehicles, anonymity is necessary but not sufficient to thwart tracking an attack that aims at the drivers’ location profiles. Thus, several location privacy protection mechanisms based on pseudonymity are elaborated to further protect the vehicles’ privacy and guarantee the quality of location-based services simultaneously. We also give a comprehensive analysis on various trust management models in VANETs. Finally, considering that current and near-future applications in VANETs are evaluated by simulation, we give a much-needed update on the latest mobility and network simulators as well as the integrated simulation platforms. In sum, this paper is carefully positioned to avoid overlap with existing surveys by filling the gaps and reporting the latest advances in VANETs while keeping it self-explained.

A Survey on Recent Advances in Vehicular Network Security, Trust, and Privacy

Vehicular ad hoc networks (VANETs) have stimulated interest in both academic and industry settings because, once deployed, they would bring a new driving experience to drivers. However, communicating in an open-access environment makes security and privacy issues a real challenge, which may affect the large-scale deployment of VANETs. Researchers have proposed many solutions to these issues. We start this paper by providing background information of VANETs and classifying security threats that challenge VANETs. After clarifying the requirements that the proposed solutions to security and privacy problems in VANETs should meet, on the one hand, we present the general secure process and point out authentication methods involved in these processes. Detailed survey of these authentication algorithms followed by discussions comes afterward. On the other hand, privacy preserving methods are reviewed, and the tradeoff between security and privacy is discussed. Finally, we provide an outlook on how to detect and revoke malicious nodes more efficiently and challenges that have yet been solved.

A Security and Privacy Review of VANETs

In vehicular ad hoc networks (VANETs), trust establishment among vehicles is important to secure integrity and reliability of applications. In general, trust and reliability help vehicles to collect correct and credible information from surrounding vehicles. On top of that, a secure trust model can deal with uncertainties and risk taking from unreliable information in vehicular environments. However, inaccurate, incomplete, and imprecise information collected by vehicles as well as movable/immovable obstacles have interrupting effects on VANET. In this paper, a fuzzy trust model based on experience and plausibility is proposed to secure the vehicular network. The proposed trust model executes a series of security checks to ensure the correctness of the information received from authorized vehicles. Moreover, fog nodes are adopted as a facility to evaluate the level of accuracy of event’s location. The analyses show that the proposed solution not only detects malicious attackers and faulty nodes, but also overcomes the uncertainty and imprecision of data in vehicular networks in both line of sight and non-line of sight environments.

A Secure Trust Model Based on Fuzzy Logic in Vehicular Ad Hoc Networks With Fog Computing

Cooperative Intelligent Transportation Systems, mainly represented by vehicular ad hoc networks (VANETs), are among the key components contributing to the Smart City and Smart World paradigms. Based on the continuous exchange of both periodic and event triggered messages, smart vehicles can enhance road safety, while also providing support for comfort applications. In addition to the different communication protocols, securing such communications and establishing a certain trustiness among vehicles are among the main challenges to address, since the presence of dishonest peers can lead to unwanted situations. To this end, existing security solutions are typically divided into two main categories, cryptography and trust, where trust appeared as a complement to cryptography on some specific adversary models and environments where the latter was not enough to mitigate all possible attacks. In this paper, we provide an adversary-oriented survey of the existing trust models for VANETs. We also show when trust is preferable to cryptography, and the opposite. In addition, we show how trust models are usually evaluated in VANET contexts, and finally, we point out some critical scenarios that existing trust models cannot handle, together with some possible solutions.

Trust Management for Vehicular Networks: An Adversary-Oriented Overview

Security and privacy will play a pivotal role in the commercialization of Vehicular Ad-hoc NETworks (VANETs). Traditionally, both cryptographic and non-cryptographic approaches have been used by researchers to address security and privacy issues and achieve secure Intelligent Transportation System (ITS) applications. However, some security goals such as trust and reputation, are still hard to achieve through conventional cryptographic approaches. Trust is the degree of certainty with which the received information is accepted and acted upon. Historically trust has been computed for both the content generator and the content itself with former known as entity trust and the latter known as data trust. Both entity and content trust are equally important to support trustworthy communication in VANET. We review, analyze, and compare some of the recently proposed trust establishment and management mechanisms (from 2014 to 2019) in vehicular networks. Furthermore, we also discuss the weaknesses and inadequacies of existing trust establishment and management approaches when deployed in a VANET environment. Finally, we discuss some future challenges that will need to be addressed for trustworthy communications in vehicular networks.

Trust in VANET: A Survey of Current Solutions and Future Research Opportunities

The basis of vehicular ad hoc networks (VANETs) is the exchange of data between entities, and making a decision on received data/event is usually based on information provided by other entities. Many researchers utilize the concept of trust to assess the trustworthiness of the received data. Nevertheless, the lack of a review to sum up the best available research on specific questions on trust management in vehicular ad hoc networks is sensible. This paper presents a systematic literature review to provide comprehensive and unbiased information about various current trust conceptions, proposals, problems, and solutions in VANETs to increase quality of data in transportation. For the purpose of the writing of this paper, a total of 111 articles related to the trust model in VANETs published between 2005 and 2014 were extracted from the most relevant scientific sources (IEEE Computer Society, ACM Digital Library, Springer Link, Science Direct, and Wiley Online Library). Finally, ten articles were eventually analyzed due to several reasons such as relevancy and comprehensiveness of discussion presented in the articles. Using the systematic method of review, this paper succeeds to reveal the main challenges and requirements for trust in VANETs and future research within this scope.

/pdf/trust-management-in-vehicular-ad-hoc-network-a-systematic-1jt76q1ge6.pdf

Trust management in vehicular ad hoc network: a systematic review

The deployment of vehicular communication systems is strongly dependent on their security. In fact, security plays a vital role in Vehicular Ad hoc network (VANET). This paper presents a systematic literature review to provide comprehensive and unbiased information about various current model security conceptions, proposals, problems and solutions in VANET for safety transportation. For this purpose, a total of 186 articles related to the security model in VANET published between 2006 and 2013 were extracted from the most relevant scientific sources (IEEE Computer Society, ACM Digital Library, Springer Link and ScienceDirect). However, 24 articles were eventually analyzed due to several reasons such as relevancy and comprehensiveness of discussion presented in the articles. Using the systematic method of review, this paper succeeds to reveal the main security threats, challenges for security, security requirement in VANET and future research within this scope.

A systematic review of security in vehicular ad hoc network

Continuous authentication for VANET

Standards such as the American IEEE 1609, European ETSI ITS-G5, and Japanese ARIB STD-T109 aim to establish Cooperative Intelligent Transportation Systems (C-ITS) by enabling Vehicular Ad-Hoc Networks (VANETs). In VANETs, vehicles communicate with other vehicles and roadside infrastructure to support latency-critical applications which increase driver awareness of the surroundings. This should result in improved safety and possibly optimizing traffic. However, to secure VANET communications against message manipulation or replaying, security standards such as IEEE 1609.2 and ETSI TS 103 097 are proposed. In this work, we implement the cryptographic primitives recommended in the IEEE 1609.2 standard to authenticate low latency safety critical messages. We evaluate the effect of the implementation using metrics such as CPU clock cycles per operation, average computation time in milliseconds, and message size in bits. We perform a simulation presenting a high-density highway scenario for the above mentioned C-ITS standards. For each standard, we evaluate the number of safety messages that can be successfully received within 100 ms latency. We show how and to what extent the authentication overhead of latency-critical messages may impact on driver safety. Under an assumed traffic scenario, we show that a crash is possible, as a result of the evaluated authentication delay. We show that the recommended algorithms with specific parameters can be a potential solution for low latency safety-critical applications in a large scale scenario.

/pdf/broadcast-authentication-in-latency-critical-applications-on-4s38fl3b4i.pdf

Broadcast Authentication in Latency-Critical Applications: On the Efficiency of IEEE 1609.2

In the near future, intelligent vehicles will be connected via wireless communication links, forming Vehicular Ad-hoc Networks (VANETs). This has potential to improve road safety and to optimize traffic. However, if the communications are not secure, VANETs are vulnerable to cyber attacks involving message manipulation. Research on this problem has produced multiple authentication protocols based on bilinear pairings (a variant of elliptic curve cryptography). The efficiency of such authentication schemes must be addressed before they can be used in real-world deployments. Standards bodies have begun standardizing various pairing-based schemes. The IEEE 1609.2 security standard has not yet selected any pairing-based scheme, leaving the settings related to pairing-based cryptography in the vehicular environments unspecified. In this work, we investigate the efficiency of pairing-based cryptographic primitives over the Barreto-Lynn-Scott and Barreto-Naehrig pairing friendly elliptic curves recommended in the IETF and ISO standards, to determine their suitability for practical application. We implement the algorithms and evaluate the effect of cryptographic pairings using theoretical and experimental analysis of four well-known pairing-based short signature schemes, including: Boneh-Lynn-Shacham, Boneh-Boyen, Zhang-Safavi-Susilo, and Boneh-Gentry-Lynn-Shacham. We use metrics including CPU clock cycles per operation, average computation time in milliseconds, and signature/public key size in bits to estimate the cost of implementing cryptographic pairings on modern processors. We demonstrate the effect of pairing-based cryptography on authentication in vehicular networks. We investigate a high-density highway scenario and show that a crash is possible, as a result of the evaluated authentication delay. We share our findings ahead of the IEEE 1609.2 recommendations for the use of cryptographic pairings.

/pdf/on-the-efficiency-of-pairing-based-authentication-for-qt1up0rl62.pdf

Mir Ali Rezazadeh Baee

Papers

Trust management in vehicular ad hoc network: a systematic review

A systematic review of security in vehicular ad hoc network

Continuous authentication for VANET

Broadcast Authentication in Latency-Critical Applications: On the Efficiency of IEEE 1609.2

On the Efficiency of Pairing-Based Authentication for Connected Vehicles: Time is Not on Our Side!