Privacy In Vehicular Ad Hoc Networks Research Articles

A Survey on Pseudonym Changing Strategies for Vehicular Ad-Hoc Networks

The initial phase of the deployment of Vehicular Ad-Hoc Networks (VANETs) has begun and many research challenges still need to be addressed. Location privacy continues to be in the top of these challenges. Indeed, both of academia and industry agreed to apply the pseudonym changing approach as a solution to protect the location privacy of VANETs'users. However, due to the pseudonyms linking attack, a simple changing of pseudonym shown to be inefficient to provide the required protection. For this reason, many pseudonym changing strategies have been suggested to provide an effective pseudonym changing. Unfortunately, the development of an effective pseudonym changing strategy for VANETs is still an open issue. In this paper, we present a comprehensive survey and classification of pseudonym changing strategies. We then discuss and compare them with respect to some relevant criteria. Finally, we highlight some current researches, and open issues and give some future directions.

LIAP: A local identity-based anonymous message authentication protocol in VANETs

In vehicular ad hoc networks (VANETs), vehicle communicates with other nodes through an open wireless channel, which raises many potential safety issues. Both the public key infrastructure (PKI) and identity based authentication protocols can meet the requirements of security and privacy of VANETs. However, the receiver needs to check certificate revocation list (CRL) before certificate and signature verification in PKI-base schemes. The additional CRL checking reduces the authentication efficiency. In the identity-based schemes, every vehicle holds too many valid identities in order to protect privacy. It is complicated to revoke the membership of vehicle. To cope with the inherent issues, we propose a local identity-based anonymous message authentication protocol (LIAP) for VANETs, in which each vehicle and road side unit (RSU) is assigned a unique long term certification from the certificate authority (CA) in registration phase. RSU is in charge of managing and assigning the local master keys to every vehicle of entering its communication range. When vehicle meets a new RSU, they authenticate each other by their long certificates. The valid vehicle can obtain the local master keys from current RSU to generate the localized anonymous identity. To protect privacy, vehicle randomly chooses the anonymous identity to sign the safety-related message, which can be efficiently verified by the single or batch authentication manner. Finally, performance analysis and simulation show that LIAP is effective in terms of authentication speed and communication overhead.

EAAP: Efficient Anonymous Authentication With Conditional Privacy-Preserving Scheme for Vehicular Ad Hoc Networks

Providing an efficient anonymous authentication scheme in vehicular ad hoc networks (VANETs) with low computational cost is a challenging issue. Even though, there are some existing schemes to provide anonymous authentication, the existing schemes suffer from high computational cost in the certificate and the signature verification process, which leads to high message loss. Therefore, they fail to meet the necessity of verifying hundreds of messages per second in VANETs. In our scheme, we propose an efficient anonymous authentication scheme to avoid malicious vehicles entering into the VANET. In addition, the proposed scheme offers a conditional tracking mechanism to trace the vehicles or roadside units that abuse the VANET. As a result, our scheme revokes the privacy of misbehaving vehicles to provide conditional privacy in a computationally efficient way through which the VANET entities will be anonymous to each other until they are revoked from the VANET system. Moreover, the proposed scheme is implemented and the performance analysis shows that our scheme is computationally efficient with respect to the certificate and the signature verification process by keeping conditional privacy in VANETs.

Computationally efficient privacy preserving anonymous mutual and batch authentication schemes for vehicular ad hoc networks

In the near future, it is envisioned that vehicular Ad hoc networks (VANETs) will be making use of long-distance communication techniques, such as cellular networks and Worldwide Interoperability for Microwave Access (WiMAX), to get instant Internet access for making the communication between vehicles and fixed road side infrastructure. Moreover, VANETs will also make use of short-distance communication methods, such as Dedicated Short-Range Communications (DSRC) and Wireless Fidelity (Wi-Fi) to perform short range communication between vehicles in an ad hoc manner. This Internet connection can provide facility to other vehicles to send traffic related messages, collisions, infotainment messages other useful safety alerts. In such a scenario, providing authentication between vehicle to infrastructure and vehicle to vehicle is a challenging task. In order to provide this facility, in this paper, we propose a computationally efficient privacy preserving anonymous authentication scheme based on the use of anonymous certificates and signatures for VANETs in making them an important component of Internet of Things (IoT) and the development of smart cities. Even though there are several existing schemes available to provide such anonymous authentication based on anonymous certificates and signatures in VANETs, the existing schemes suffer from high computational cost in the certificate revocation list (CRL) checking process and in the certificate and the signature verification process. Therefore, it is not possible to verify a large number of messages in a particular period in VANETs which would lead to increased message loss. Hence, we use a computationally efficient anonymous mutual authentication scheme to validate the message source as well as to verify the integrity of messages along with a conditional tracking mechanism to trace the real identity of misbehaving vehicles and revoke them from VANET in the case of dispute. In this paper, we also introduce an efficient anonymous batch authentication protocol to be used in IoT for Road Side Units (RSUs) to authenticate multiple vehicles simultaneously rather than one after the other such that the total authentication time can be dramatically reduced. This proposed scheme is implemented and the performance analysis shows that our scheme is more efficient in terms of certificate and signature verification cost, while preserving conditional privacy in VANETs.

Design of a VANET privacy and non‐repudiation accident reporting system

AbstractAs network technology has rapidly developed over recent years, more research into vehicular ad hoc networks (VANETs) has come to highlight security and privacy issues within these networks. In discussions on security issues, the attempt by VANETs to ensure driver privacy makes non‐repudiation extremely difficult; many studies on security have failed to discuss this important issue. Vehicle drivers' privacy is weighed against sender non‐repudiation; these two factors are generally regarded as being in opposition. Because accident reporting systems will aim to retain complete privacy, they may be unable to guarantee non‐repudiation. This study therefore uses mutual authentication, digital signatures, and authorization certificates to develop an accident reporting system for VANETs which is not only able to retain driver privacy but also to track dangerous behavior on the part of drivers. Copyright © 2016 John Wiley & Sons, Ltd.

An Efficient Anonymous Batch Authentication Scheme Based on HMAC for VANETs

In vehicular ad hoc networks (VANETs), when a vehicle receives a message, the certificate revocation list (CRL) checking process will operate before certificate and signature verification. However, large communication sources, storage space, and checking time are needed for CRLs that cause the privacy disclosure issue as well. To address these issues, in this paper, we propose an efficient anonymous batch authentication scheme (ABAH) to replace the CRL checking process by calculating the hash message authentication code (HMAC). In our scheme, we first divide the precinct into several domains, in which road-side units (RSUs) manage vehicles in a localized manner. Then, we adopt pseudonyms to achieve privacy-preserving and realize batch authentication by using an identity-based signature (IBS). Finally, we use HMAC to avoid the time-consuming CRL checking and to ensure the integrity of messages that may get loss in previous batch authentication. The security and performance analysis are carried out to demonstrate that ABAH is more efficient in terms of verification delay than the conventional authentication methods employing CRLs. Meanwhile, our solution can keep conditional privacy in VANETs.

TAPCS: Traffic-aware pseudonym changing strategy for VANETs

Location privacy is one of the main challenges in Vehicular Ad-hoc Networks (VANETs), since weak protection may hinder the public acceptance of this technology. Frequently changing pseudonyms are commonly accepted as a solution to protect the location privacy in VANETs. However, a simple pseudonym change is not enough to provide the required protection. Although many pseudonym changing strategies have been proposed to enhance the location privacy protection provided by this approach, the development of an effective strategy is not yet achieved. In this paper, we propose a new pseudonym changing strategy called Traffic-Aware Pseudonym Changing Strategy (TAPCS). The aim of this strategy is to provide an effective location privacy protection against the different types of pseudonyms linking attacks that can be performed by a strong passive adversary model. TAPCS is a distributed pseudonym changing strategy and is one of the strategies that use the radio silence technique. Unlike the existing distributed pseudonym changing strategies that use this technique, TAPCS aims to provide a high level of location privacy protection without impacting the safety in the VANETs. The analytical evaluation and simulation results demonstrate the effectiveness of the proposed strategy.

A Secure Hash Message Authentication Code to Avoid Certificate Revocation List Checking in Vehicular Adhoc Networks

A secure hash message authentication code to avoid certificate revocation list checking is proposed for vehicular ad hoc networks (VANETs). The group signature scheme is widely used in VANETs for secure communication, the existing systems based on group signature scheme provides verification delay in certificate revocation list checking. In order to overcome this delay this paper uses a Hash message authentication code (HMAC). It is used to avoid time consuming CRL checking and it also ensures the integrity of messages. The Hash message authentication code and digital signature algorithm are used to make it more secure . In this scheme the group private keys are distributed by the roadside units (RSUs) and it also manages the vehicles in a localized manner. Finally, cooperative message authentication is used among entities, in which each vehicle only needs to verify a small number of messages, thus greatly alleviating the authentication burden. The security and performance analysis show that our scheme is more efficient in terms of authentication speed, while keeping conditional privacy in VANETs.

Improving the Authentication Scheme and Access Control Protocol for VANETs

Privacy and security are very important in vehicular ad hoc networks (VANETs). VANETs are negatively affected by any malicious user’s behaviors, such as bogus information and replay attacks on the disseminated messages. Among various security threats, privacy preservation is one of the new challenges of protecting users’ private information. Existing authentication protocols to secure VANETs raise challenges, such as certificate distribution and reduction of the strong reliance on tamper-proof devices. In 2011, Yeh et al. proposed a PAACP: a portable privacy-preserving authentication and access control protocol in vehicular ad hoc networks. However, PAACP in the authorization phase is breakable and cannot maintain privacy in VANETs. In this paper, we present a cryptanalysis of an attachable blind signature and demonstrate that the PAACP’s authorized credential (AC) is not secure and private, even if the AC is secretly stored in a tamper-proof device. An eavesdropper can construct an AC from an intercepted blind document. Any eavesdropper can determine who has which access privileges to access which service. For this reason, this paper copes with these challenges and proposes an efficient scheme. We conclude that an improving authentication scheme and access control protocol for VANETs not only resolves the problems that have appeared, but also is more secure and efficient.

Efficient Privacy-Preserving Authentication for Vehicular Ad Hoc Networks

In this paper, we present an efficient privacy-preserving authentication scheme based on group signature for vehicular ad hoc networks (VANETs). Although group signature is widely used in VANETs to realize anonymous authentication, the existing schemes based on group signatures suffer from long computation delay in the certificate revocation list (CRL) checking and in the signature verification process, leading to high message loss. As a result, they cannot meet the requirement of verifying hundreds of messages per second in VANETs. In our scheme, we first divide the precinct into several domains, in which roadside units (RSUs) are responsible for distributing group private keys and managing vehicles in a localized manner. Then, we use a hash message authentication code (HMAC) to avoid time-consuming CRL checking and to ensure the integrity of messages before batch group authentication. Finally, we adopt cooperative message authentication among entities, in which each vehicle only needs to verify a small number of messages, thus greatly alleviating the authentication burden. The security and performance analysis show that our scheme is more efficient in terms of authentication speed, while keeping conditional privacy in VANETs.

An analytical model for random pseudonym change scheme in VANETs

The emerging Vehicular Ad hoc NETworks (VANETs) can improve safety, efficiency and convenience in transportation. In spite of the expected benefits, VANETs also introduce some location privacy risk by periodically broadcasting vehicular information. Pseudonym change is commonly accepted as one approach to protect location privacy in VANETs, but the effectiveness of most pseudonym change schemes has never been investigated theoretically. In this paper, focusing on the Random Pseudonym Change (RPC) scheme, we propose an analytical model to quantify its level of location privacy by calculating the size of anonymity set of a vehicle. With this model, we can analyze the probability of a vehicle changing pseudonym simultaneously with its neighbor, which can be then used to calculate the size of anonymity set of the vehicle. Further, we investigate the influence of the pseudonym lifetime distribution on the level of location privacy. Research results, which are validated via extensive simulations, show that for the RPC scheme, the uniform pseudonym lifetime distribution can provide better location privacy protection than the reciprocal pseudonym lifetime distribution. In addition, we also discuss the conditional probability of a vehicle changing pseudonym simultaneously with its neighbor given the age of pseudonym used by the neighbor at the time when the vehicle last changed pseudonym, and point out that utilizing the age of pseudonym can improve the level of location privacy.

Pseudonym Changing at Social Spots: An Effective Strategy for Location Privacy in VANETs

As a prime target of the quality of privacy in vehicular ad hoc networks (VANETs), location privacy is imperative for VANETs to fully flourish. Although frequent pseudonym changing provides a promising solution for location privacy in VANETs, if the pseudonyms are changed in an improper time or location, such a solution may become invalid. To cope with the issue, in this paper, we present an effective pseudonym changing at social spots (PCS) strategy to achieve the provable location privacy. In particular, we first introduce the social spots where several vehicles may gather, e.g., a road intersection when the traffic light turns red or a free parking lot near a shopping mall. By taking the anonymity set size as the location privacy metric, we then develop two anonymity set analytic models to quantitatively investigate the location privacy that is achieved by the PCS strategy. In addition, we use game-theoretic techniques to prove the feasibility of the PCS strategy in practice. Extensive performance evaluations are conducted to demonstrate that better location privacy can be achieved when a vehicle changes its pseudonyms at some highly social spots and that the proposed PCS strategy can assist vehicles to intelligently change their pseudonyms at the right moment and place.

AMOEBA: Robust Location Privacy Scheme for VANET

Communication messages in vehicular ad hoc networks (VANET) can be used to locate and track vehicles. While tracking can be beneficial for vehicle navigation, it can also lead to threats on location privacy of vehicle user. In this paper, we address the problem of mitigating unauthorized tracking of vehicles based on their broadcast communications, to enhance the user location privacy in VANET. Compared to other mobile networks, VANET exhibits unique characteristics in terms of vehicular mobility constraints, application requirements such as a safety message broadcast period, and vehicular network connectivity. Based on the observed characteristics, we propose a scheme called AMOEBA, that provides location privacy by utilizing the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">group navigation of vehicles</i> . By simulating vehicular mobility in freeways and streets, the performance of the proposed scheme is evaluated under VANET application constraints and two passive adversary models. We make use of vehicular groups for anonymous access to location based service applications in VANET, for user privacy protection. The robustness of the user privacy provided is considered under various attacks.