Pseudonym Change Research Articles

PRIVANET: An Efficient Pseudonym Changing and Management Framework for Vehicular Ad-Hoc Networks

Protecting the location privacy is one of the main challenges in vehicular ad-hoc networks (VANETs). Although, standardization bodies, such as IEEE and ETSI, have adopted a pseudonym-based scheme as a solution for this problem, an efficient pseudonym changing and management is still an open issue. In this paper, we propose PRIVANET, a complete and efficient pseudonym changing and management framework. The PRIVANET has a hierarchical structure and considers the vehicular geographic area as a grid. Each cell of this grid contains one or many logical zones, called vehicular location privacy zones (VLPZs). These zones can easily be deployed over the widespread roadside infrastructures (RIs), such as gas stations, to provide a secure changing and management of pseudonyms. The proposed framework consists of different building blocks: 1) an effective VLPZ-based pseudonym changing strategy; 2) a reputation-based mechanism to motivate selfish vehicles to enter VLPZs; 3) an adapted user-centric privacy model; 4) a secure hybrid mechanism for the distribution of pseudonyms sets and CRLs; 5) a method to generate the IP and MAC addresses from the pseudonym; 6) a stochastic model to estimate the number of VLPZs required at a given cell; and 7) a mathematical model for an optimal placement of the VLPZs over RIs to reduce the transportation cost of vehicles in terms of time. An extensive simulation study using a realistic map and with real traffic mobility measurements is carried out to evaluate and validate the performance of the PRIVANET. The simulation results demonstrate the effectiveness of the proposed framework.

Mix-Context-Based Pseudonym Changing Privacy Preserving Authentication in VANETs

Vehicular ad hoc networks (VANETs) have attracted significant attention in academia insofar as they can provide reliable and secure communication between vehicles. It is thus essential to ensure security and preserve privacy. In this paper, we propose mix-context-based pseudonym changing privacy-preserving authentication (MPCPA). MPCPA introduces privacy protection through a mutual authentication mechanism to prevent attack-vehicles from sneaking into a VANET system. Moreover, it preserves the integrity of transmitted messages with an anonymous authentication mechanism. In addition, MPCPA adopts a mix-context-based pseudonym changing strategy to prevent vehicle tracking. A performance analysis demonstrates that MPCPA incurs low computational costs and offers a privacy-preserving scheme that is more secure than existing authentication schemes.

Evaluating the effectiveness of pseudonym changing strategies for location privacy in vehicular ad‐hoc network

In a vehicular ad‐hoc network, vehicles periodically broadcast safety messages to neighboring vehicles containing information about their identity, location, speed, and other relevant information. The time‐critical nature of these messages means they are typically sent without encryption, which can compromise the privacy of the vehicle/driver. The use of pseudonyms, rather than the actual identity, has been suggested as a way to implement location privacy for drivers. However, such pseudonyms need to change frequently in order to prevent vehicle tracking. A pseudonym changing strategy (PCS) determines how frequently and under which conditions a vehicle should change its pseudonym. Many different PCS have been proposed in the literature over the last decade. However, there is a lack of a systematic analysis of the performance of these techniques, using a set of well‐defined privacy metrics. In this article, we provide a thorough comparison of four main types of PCS, in terms of standard privacy metrics, and identify the advantages and limitations of each approach under different traffic conditions and attacker capabilities. The ultimate aim of this study is to help in the determination of the best PCS to use in different situations, to maximize the location privacy.

An effective variant ring signature-based pseudonym changing mechanism for privacy preservation in mixed zones of vehicular networks

The privacy information related to the location of the vehicles need to be concealed with utmost care in the vehicular network since its disclosure leads to a diversified number of attacks that degrades the performance of the network. But, the privacy of vehicles relies on a kind of pseudonym changing mechanism utilized in the mix zone of the vehicular networks. However, the strength of location privacy is influenced by the lower vehicular density and characteristics of decentralization in the mixed zone. In this paper, an effective variant ring signature-based pseudonym changing mechanism (EVRS-PCM) is contributed for privacy preservation under decentralization and reduced density of vehicles. This proposed EVRS-PCM approach uses a ring signature-based pseudonym changing procedure that potentially minimizes the number of pseudonyms notifications under the formation of mixed zones in the network for facilitating excellent location privacy. The results of the proposed EVRS-PCM approach confirmed an optimal rate of success rate, location privacy and the percentage decrease in the number of pseudonym notifications under the varying proportion of mixed zones, distances and vehicles in the network.

Pseudonym Management Through Blockchain: Cost-Efficient Privacy Preservation on Intelligent Transportation Systems

Research into the established area of the intelligent transportation system is evolving into the Internet of Vehicles, a fast-moving research area, fuelled in part by rapid changes based on cyber-physical systems. It needs to be recognized that existing vehicular communication systems are susceptible to privacy vulnerabilities which require addressing. A practical challenge is that many vehicular communication applications and services make use of basic safety messages that contain the identity of the vehicle, location, and other personal data. A popular way of dealing with this privacy issue is to utilize a pseudonym change scheme to protect the vehicle's identity and location. However, many such schemes suffer that the cost grows and the certificate management difficulty raises with the number of pseudonyms generated and stored, casting doubt of the economic feasibility of that approach. We propose a decentralized blockchain-based solution for pseudonym management that overcomes these limitations. This scheme consists of pseudonym distribution and a shuffle operation, allowing the reuse of existing pseudonyms to different vehicles. The results reported here, including those from our simulations, demonstrate that the proposed scheme can reuse existing pseudonyms and achieve a better degree of anonymity at a lower cost than existing schemes.

An Evaluation of Pseudonym Changes for Vehicular Networks in Large-Scale, Realistic Traffic Scenarios

Changing pseudonym certificates are the agreed-upon approach for privacy-friendly message authentication in upcoming vehicular ad hoc networks and are included in recent standards. This paper examines the performance of four different pseudonym change strategies and their parameters using simulations of realistic, large-scale traffic scenarios. The strategies are assessed by measuring their effectiveness and efficiency in protecting drivers from being tracked by an attacker with limited coverage. In an urban scenario, all strategies achieve satisfactory privacy protection, but the change frequency required is rather high. In a highway scenario, the attacker algorithm achieves a high-tracking success for all strategies, especially in low traffic, even for very short change intervals. This paper proposes concrete change intervals for urban scenarios, which are higher than currently foreseen, but concludes that privacy protection in uniform traffic conditions remains a challenge.

RIN: A dynamic pseudonym change system for privacy in VANET

SummaryWe propose in this paper a security protocol based on a dynamic change of pseudonym for privacy and anonymity in Vehicular Ad hoc NETworks (VANET). Our proposal ensures privacy for the driver and his vehicle whether he is the transmitter or receiver of the message. By handling all possible cases of changes in vehicles behavior during traffic, we ensure a safe and secure traffic management. We built the architecture of our solution on three essential entities designed for VANET: a trusted authority, a Road Side Unit, and vehicles. Our pseudonym change system ensures anonymity at any time, anywhere, with any speed of a vehicle, in all directions of a vehicle, in any environment (highway or urban), with any traffic density, independently of neighboring vehicles, and changes in vehicles behavior. In three steps, anonymity, integrity, and confidentiality are guaranteed by our RIN (Real Initial New) protocol. Our protocol blocks attacks as DOS and Sybil. Results obtained by the simulations show the efficiency of our solution. Compared with other relevant approaches from the literature, the results confirm the credibility of our protocol regarding to the privacy assurance in VANET.

An incentive-based co-operation motivating pseudonym changing strategy for privacy preservation in mixed zones in vehicular networks

Location privacy of the vehicles is considered as the potential information that needs to be protected with maximum care in the vehicular network. This location privacy depends on the method of the pseudonym strategy scheme adopted in the mix zone of vehicular networks. The maximum degree of privacy is required in the mixed zone because the decentralization and lower vehicular density of vehicles in the mixed zone have the maximum probability of reducing the strength of facilitating location privacy. However, location privacy in the mixed zone depends on the number of cooperative vehicles interacting within the spatio temporal environment. In this paper, an incentive-based co-operation motivating pseudonym changing strategy for privacy preservation in mixed zones is proposed for resolving the issue of pseudonym change and influence of cooperative vehicle density. This proposed mechanism uses a one-way hash function and an improved pseudonym scheme for estimating vehicular incentives in order to facilitate privacy protection. The extensive investigation of the proposed mechanism is confirmed to be excellent in terms of location privacy under different distances, a number of vehicles and the number of mixed zones compared to the pseudonym changing privacy preservation schemes proposed for addressing privacy in mixed zones of vehicular networks.

Privacy-Preserved Pseudonym Scheme for Fog Computing Supported Internet of Vehicles

As a promising branch of Internet of Things, Internet of Vehicles (IoV) is envisioned to serve as an essential data sensing and processing platform for intelligent transportation systems. In this paper, we aim to address location privacy issues in IoV. In traditional pseudonym systems, the pseudonym management is carried out by a centralized way resulting in big latency and high cost. Therefore, we present a new paradigm named Fog computing supported IoV (F-IoV) to exploit resources at the network edge for effective pseudonym management. By utilizing abundant edge resources, a privacy-preserved pseudonym ( $P^{3}$ ) scheme is proposed in F-IoV. The pseudonym management in this scheme is shifted to specialized fogs at the network edge named pseudonym fogs, which are composed of roadside infrastructures and deployed in close proximity of vehicles. $P^{3}$ scheme has following advantages: 1) context-aware pseudonym changing; 2) timely pseudonym distribution; and 3) reduced pseudonym management overhead. Moreover, a hierarchical architecture for $P^{3}$ scheme is introduced in F-IoV. Enabled by the architecture, a context-aware pseudonym changing game and secure pseudonym management communication protocols are proposed. The security analysis shows that $P^{3}$ scheme provides secure communication and privacy preservation for vehicles. Numerical results indicate that $P^{3}$ scheme effectively enhances location privacy and reduces communication overhead for the vehicles.

A RSU-aided distributed trust framework for pseudonym-enabled privacy preservation in VANETs

Vehicular ad hoc networks (VANETs) have the potential to change the way of people drive, travel and so on, in which vehicle can broadcast and forward the message of road condition or emergency. When the received messages are unreliable, they may lead the vehicles to make wrong decisions. To assess how trustworthy the messages are, every vehicle holds the reputation value in the trust-based schemes. In pseudonym-based schemes, vehicles change their pseudonyms by some kind of manner to confuse the trackers. However, the reputation value provides an additional clue to track vehicle when it and the pseudonym change asynchronously. To reconcile the conflict of privacy preservation and reputation evaluation, we propose a distributed trust framework for pseudonym-enabled privacy preservation in VANETs. In this framework, the road side unit assigns the reputation label certificate (RLC) to evaluate the reliability of message for every vehicle in its communication range. To preserve the privacy, the RLC manifests two trust statuses to replace the specific reputation value. All the reputation values of vehicles are stored in the centrical database. To encourage vehicle to follow the rules, the reputation update algorithm is designed with different weights, which achieve the reputation value increasing slowly and decreasing quickly. When RLC of vehicle is revoked, its security and privacy will not be protected. Finally, theoretical analysis and simulations show that our scheme can efficiently meet the requirements of security and privacy in VANETs.

Independent Mix Zone for Location Privacy in Vehicular Networks

The sensitive information of vehicles is related to location in vehicular networks. Pseudonym change is an effective way to protect the location privacy of vehicles, which is to establish a specific area called mix zone, where at least $k$ number of vehicles change pseudonyms together to obtain $k$ anonymity. However, it depends on the number of collaborative ones in spatiotemporal context. To solve the pseudonym change problem in the low density of vehicles, an independent mix zone scheme, shorted for indMZ, is proposed in this paper. It specifies a pseudonym scheme for the vehicular networks, which consists of the procedures of certification issuance and pseudonym issuance. Each vehicle will have $L$ pseudonyms when it enrolls to a road side units. As a pseudonym is about to be expired, the vehicle can establish a mix zone through beacon messages which are inherently broadcasted in neighborhood periodically. The independent mix zone means that each of the collaborative vehicles will produce some randomized versions of a pseudonym, respectively, and contribute to the desired $k$ -anonymous mix zone. Even in the worst case of zero collaborator, the vehicle can still establish a $k$ anonymous pseudonym change region all by itself. We evaluate indMZ and other mix zone schemes with respective to the performance and strength of location privacy in the low density of vehicular networks. It shows that indMZ can ensure $k$ anonymity with $k/2$ average cost of extended beacon message and be independent on any trusted third party.

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.

CLPS: context-based location privacy scheme for VANETs

Location privacy preservation is considered as a challenge for deploying vehicular ad hoc networks (VANETs). In fact, the continuous periodical broadcast of spatiotemporal information in beacons allows a global passive adversary (GPA) to link pseudonyms and reconstruct vehicle traces. Consequently, it is imperative that a vehicle selects the right context to change pseudonym to confuse the adversary and ensure pseudonyms unlinkability. In this paper, we propose a context-based location privacy scheme (CLPS) that makes the following contributions: i) a pseudonym changing strategy that allows a vehicle to change pseudonyms based on its context; ii) a linkability threat, called cheating attack that negatively affects the proposed pseudonym changing strategy. A cheating detection mechanism is developed to allow a vehicle to detect misbehaving vehicles that launch the cheating attack, and assess the success of the pseudonym change. Finally, we evaluate CLPS against GPA by simulations using privacy extension, PREXT, in Veins, and we compare it against different existing privacy schemes.

Pseudonym changing strategy with multiple mix zones for trajectory privacy protection in road networks

SummaryIn road network, vehicles' location may be identified, and their transmissions may even tracked by eavesdrops (eg, safety messages) that contain sensitive personal information such as identity and location of the vehicle. This type of communication leads to breaking the users' trajectory privacy. Frequently changing pseudonyms are widely accepted as a solution that protects the trajectory privacy of users in road networks. However, this solution may become invalid if a vehicle changes its pseudonym at an improper occasion. To cope with this issue, we presented an efficient pseudonym change strategy with multiple mix zones scheme to provide trajectory privacy for road network. In addition, we protected vehicles against linkability attack by cheating mechanism. Henceforth, we constructed a cheating detection mechanism which allows the vehicles to verify whether the pseudonym change process is successful or not and also detect to malicious vehicles. In this way, users' trajectory privacy can be improved. Finally, by taking the anonymity set size (ASS) as the trajectory privacy metric, we exhibit by means of simulations that the proposed scheme is effective in multiple networks scenarios.

RETRACTED ARTICLE: Location Privacy with Dynamic Pseudonym-Based Multiple Mix-Zones Generation over Road Networks

According to the recent studies, application related with safety associated with road networks must need verification of entities and messages. However, security of road network users like vehicles and drivers needs to be dealt with. Unique identity like pen names and certificates might get useful to ensure security. Pseudonym names and the special certificates are being considered as the basic building blocks to ensure security requirements for road networks. Nevertheless, apart from the seen advantages, road network communication might also generate certain privacy issues by giving opportunity to invader to track vehicles. One and for most basic technique is to solve this issue by means of using pen names by the vehicles and alter them time to time. Since executing the procedure of changing pen names has to increase overhead. By looking at such type of limitations, our given technique will produce top privacy level for the road network users by using dynamic pseudonyms based multiple mix zones scenario. This pseudonym based procedure will base upon vehicle’s acceleration, heading and displacement to execute dynamic pseudonym alteration. We have performed simulation by applying SUMO simulator. After having a detailed comparison with the current pseudonym change techniques, it has been verified that our given technique has shown enhanced performance in terms of acquiring top level privacy rate having few numbers of pseudonyms alteration; broad level of simulations and analysis has been elaborated the efficiency of the given technique.

From Social Group Utility Maximization to Personalized Location Privacy in Mobile Networks

With increasing popularity of location-based services (LBSs), there have also been growing concerns for location privacy. To protect location privacy in an LBS, mobile users in physical proximity can work in concert to collectively change their pseudonyms, in order to hide spatial-temporal correlation in their location traces. In this paper, we leverage mobile users' social tie structure to motivate them to participate in pseudonym change. Drawing on a social group utility maximization framework, we cast users' decision making of whether to change pseudonyms as a socially aware pseudonym change game (SA-PCG). The SA-PCG further assumes a general anonymity model that allows a user to have its specific anonymity set for personalized location privacy. For the SA-PCG, we show that there exists a socially aware Nash equilibrium (SNE), and quantify the system efficiency of SNEs with respect to the optimal social welfare. Then, we develop a greedy algorithm that myopically determines users' strategies, based on the social group utility derived from only the users whose strategies have already been determined. We show that this algorithm efficiently finds an SNE that enjoys desirable properties: 1) it is socially aware coalition-proof, and thus is also Pareto-optimal; 2) it achieves higher social welfare than any SNE for the socially oblivious pseudonym change game. We further quantify the system efficiency of this SNE with respect to the optimal social welfare. We also show that this SNE can be achieved in a distributed manner. Numerical results using real data corroborate that social welfare can be significantly improved by exploiting social ties.

Privacy protection with dynamic pseudonym-based multiple mix-zones over road networks

In this research we proposed a strategy for location privacy protection which addresses the issues related with existing location privacy protection techniques. Mix-Zones and pseudonyms are considered as the basic building blocks for location privacy; however, continuously changing pseudonyms process at multiple locations can enhance user privacy. It has been revealed that changing pseudonym at improper time and location may threat to user’s privacy. Moreover, certain methods related to pseudonym change have been proposed to attain desirable location privacy and most of these solutions are based upon velocity, GPS position and direction of angle. We analyzed existing methods related to location privacy with mix zones, such as RPCLP, EPCS and MODP, where it has been observed that these methods are not adequate to attain desired level of location privacy and suffered from large number of pseudonym changes. By analyzing limitations of existing methods, we proposed Dynamic Pseudonym based multiple mix zone (DPMM) technique, which ensures highest level of accuracy and privacy. We simulate our data by using SUMO application and analysis results has revealed that DPMM outperformed existing pseudonym change techniques and achieved better results in terms of acquiring high privacy with small number of pseudonym change.

A trigger-based pseudonym exchange scheme for location privacy preserving in VANETs

Location privacy plays an important role in Vehicular Ad Hoc Networks (VANETs). Pseudonym is normally used to preserve location privacy, which can meet the requirements of both privacy and security. When the same pseudonym is constantly used for a vehicle, the adversary can easily track it. To improve location privacy, a lot of pseudonym change schemes have been proposed. However, the tracker can match vehicles by the beacon message when it has found that the pseudonym is changed. Besides, every vehicle must hold lots of pseudonyms to change in these schemes. In this paper, we propose a trigger-based pseudonym exchange scheme, which aims to thwart to track vehicle from the sending beacons and reduce the storage consumption. We propose two trigger-based algorithms to decide when and how a vehicle exchange pseudonym with others. To evaluate the performance of our scheme, we conduct the probability of exchanging pseudonym in a road segment and a traffic intersection, and measure the tracking percent by an empirical tracker. The simulation results show that our scheme is resilient to confuse the tracker efficiently.

Urban pseudonym changing strategy for location privacy in VANETs

The development of an effective pseudonym changing strategy to protect the location privacy of the vehicular adhoc network's VANET's users is still an open problem in the literature. In this paper, we first propose a comparison between the existing pseudonym changing strategies. This comparison is based on their effectiveness to prevent the pseudonyms linking attacks and based on the costs involved in changing a pseudonym. We also propose a new pseudonym changing strategy adapted for the urban environment, called urban pseudonym changing strategy UPCS. UPCS is based on the construction of silent mix zones SMs at signalised intersections. UPCS can be configured to use either pseudonyms changing technique or pseudonyms exchanging technique inside these SMs. The analyses show a good level of prevention against the pseudonyms linking attacks. The performances are evaluated in various vehicular scenarios. The obtained results show high levels of location privacy protection can be achieved using UPCS with pseudonyms changing configuration.

Urban pseudonym changing strategy for location privacy in VANETs

The development of an effective pseudonym changing strategy to protect the location privacy of the vehicular adhoc network's (VANET's) users is still an open problem in the literature. In this paper, we first propose a comparison between the existing pseudonym changing strategies. This comparison is based on their effectiveness to prevent the pseudonyms linking attacks and based on the costs involved in changing a pseudonym. We also propose a new pseudonym changing strategy adapted for the urban environment, called urban pseudonym changing strategy (UPCS). UPCS is based on the construction of silent mix zones (SMs) at signalised intersections. UPCS can be configured to use either pseudonyms changing technique or pseudonyms exchanging technique inside these SMs. The analyses show a good level of prevention against the pseudonyms linking attacks. The performances are evaluated in various vehicular scenarios. The obtained results show high levels of location privacy protection can be achieved using UPCS with pseudonyms changing configuration.