Conditional Privacy-preserving Authentication Research Articles

Analysis and Improvement of a Conditional Privacy-Preserving Authentication Scheme With Double-Insurance in VANETs

Analysis and Improvement of a Conditional Privacy-Preserving Authentication Scheme With Double-Insurance in VANETs

Lightweight consortium blockchain-enabled secured Vehicular ad Hoc Network using certificateless conditional privacy-preserving authentication mechanism.

Towards the intelligent transportation systems, Location Based Service (LBS) are widely engaged in Vehicular Ad Hoc Networks (VANETs) that are becoming as significant application that change the human driving experience in today's world. LBS systems facilitate the users with intelligent services by collecting an accurate location information. Due to the frequent exchange rate of the location information in an open environment, VANETs are inherently susceptible to privacy and security attacks. In past, many schemes have been proposed to ensure the privacy and security of exchanged location information; but fail to deploy in practical VANETs. At the same time, system efficiency is compromised which is another primary requirement of VANETs. Leveraging the semi-decentralized and lightweight nature of consortium blockchain technology, and Certificateless conditional privacy protection scheme to reduce the node authentication overhead, this paper introduces Consortium Blockchain assisted Certificateless Conditional Privacy Protection scheme to address the aforementioned challenges. Additionally, the proposed scheme has ability to develop anonymous regions for a particular time stamp ensuring the location privacy of vehicles. Rigorous security analysis and experiments show the practicality and resilience to various attack models, and achieve ADP 83% with maximum malicious attacks. Comparing with existing state of the art methods, the proposed scheme exhibits the privacy improvement and low computational complexity.

CHAM-CLAS: A Certificateless Aggregate Signature Scheme with Chameleon Hashing-Based Identity Authentication for VANETs

Vehicular ad hoc networks (VANETs), which are the backbone of intelligent transportation systems (ITSs), facilitate critical data exchanges between vehicles. This necessitates secure transmission, which requires guarantees of message availability, integrity, source authenticity, and user privacy. Moreover, the traceability of network participants is essential as it deters malicious actors and allows lawful authorities to identify message senders for accountability. This introduces a challenge: balancing privacy with traceability. Conditional privacy-preserving authentication (CPPA) schemes are designed to mitigate this conflict. CPPA schemes utilize cryptographic protocols, including certificate-based schemes, group signatures, identity-based schemes, and certificateless schemes. Due to the critical time constraints in VANETs, efficient batch verification techniques are crucial. Combining certificateless schemes with batch verification leads to certificateless aggregate signature (CLAS) schemes. In this paper, cryptanalysis of Xiong’s CLAS scheme revealed its vulnerabilities to partial key replacement and identity replacement attacks, alongside mathematical errors in the batch verification process. Our proposed CLAS scheme remedies these issues by incorporating an identity authentication module that leverages chameleon hashing within elliptic curve cryptography (CHAM-CLAS). The signature and verification modules are also redesigned to address the identified vulnerabilities in Xiong’s scheme. Additionally, we implemented the small exponents test within the batch verification module to achieve Type III security. While this enhances security, it introduces a slight performance trade-off. Our scheme has been subjected to formal security and performance analyses to ensure robustness.

Blockchain-based conditional privacy-preserving authentication scheme using PUF for vehicular ad hoc networks

Vehicular ad hoc networks (VANET) have been the key indispensable module of the future intelligent transportation system. Security and privacy are two essential attributes that protect the safe driving of vehicles. Over the last two decades, numerous conditional privacy-preserving authentication schemes have been presented for the VANET environment. However, existing schemes have various limitations, including security issues, high storage overhead, and frequent interactions. In order to bridge these difficulties, this work combines physically unclonable function and blockchain technology to construct a conditional privacy-preserving authentication scheme for the VANET environment. Specifically, we combine physical unclonable function and dynamic pseudonym techniques to generate unique pseudonym IDs dynamically and private keys using physical unclonable function to enhance privacy protection and resist physical attack. To reduce the number of communication rounds during the verification process, we deployed lightweight blockchain nodes to avoid direct communication between the receiver and the blockchain network. The proposed scheme demonstrates resilience against various potential attacks through comprehensive security analysis and proof. Furthermore, performance metrics indicate that our scheme outperforms similar schemes, making it suitable for resource-constrained VANET.

DCPFS: A Conditional Privacy-Preserving Authentication Scheme with Dual Cuckoo Pseudonym Filters for Vanets

With the increasing frequency of information dissemination and exchange, the attention paid to security and privacy in the Internet of Vehicles (IoV) is also on the rise. To protect user privacy, many anonymous authentication scheme have been proposed. These schemes assign pseudonyms to vehicles to hide their true identities when communicating with other vehicles or Roadside Units (RSUs). However, existing schemes also face pseudonym issues such as pseudonym abuse, high storage overhead, and low query efficiency. Motivated by this, we propose an RSU-based pseudonym assistance management scheme. In this scheme, RSUs employ dual cuckoo pseudonym filters to manage pseudonyms, effectively improving pseudonym query efficiency, preventing pseudonym abuse, and reducing storage overhead. Additionally, security and performance analyses demonstrate that the proposed protocol offers stronger security features and lower overhead. Besides, our scheme has reduced the generation time of pseudonym to only 0.0039 ms.

CPPA-RORS: A conditional privacy-preserving authentication scheme based on revocable one-time ring signature for VANETs

Vehicular ad-hoc networks (VANETs) are a wireless communication system designed to improve driving safety and traffic management, with a focus on enhancing road traffic efficiency and safety. Privacy protection is one of the crucial security challenges for VANETs. However, considering the high mobility of vehicles that frequently transmit delay-intolerant safety and informative messages, two problems exist in some ring signature-based conditional privacy-preserving authentication (CPPA) schemes for VANETs: first, vehicles cannot detect the malicious vehicles when a malicious vehicle signs a message multiple times; and second, the TAs cannot reveal vehicles’ identities when some vehicles engage in illegal activities. To address these concerns, we propose a CPPA scheme based on revocable one-time ring signature (CPPA-RORS) scheme, leveraging the properties of ring signatures. The scheme ensures anonymity of the honest vehicles while providing TAs with the ability to reveal malicious vehicles at any time. We allow one vehicle only can sign one signature on one message, called one-time, to safeguard vehicle privacy with high security. CPPA-RORS scheme provides the formal security model for VANETs, and in particular simultaneously offers message-linkability and mandatory revocability, effectively preventing the double-spending attack (Shrestha et al. 2020) and enabling TAs to revoke the anonymity of any vehicle at any time for further enhancing the security and trustworthiness of the networks. Theoretical analysis and experimental results show that CPPA-RORS provides robust security measures and privacy for vehicles in VANETs.

Hybrid cryptography-based scheme with conditional privacy-preserving authentication and memory-based DOS resilience in V2X

To secure Vehicle-to-everything (V2X) communications, many Conditional Privacy-Preserving Authentication schemes (CPPA) use symmetric and asymmetric encryption during the authentication process. However, several existing schemes have some security limitations regarding VANET requirements. In many symmetric cryptography-based schemes, the participants are required to share the same keys which could compromise the security of the network in case the key of one participant is compromised, while many asymmetric cryptography-based schemes take much time during the authentication process, and don't address the denial-of-service attack. In this paper, we propose a certificateless scheme that does not require a certificate and prevents the escrow problem. Plus, it uses the elliptic curve cryptography and avoids bilinear pairing and Map-to-Hash functions. We call our scheme Hybrid Cryptography-Based Scheme with a Conditional Privacy-Preserving Authentication (HCBS-CPPA), as it uses both symmetric and asymmetric cryptography during the authentication process. Our scheme combines the strength of an asymmetric encryption that satisfies non-repudiation, and the strength of a symmetric encryption that allows to perform a lightweight authentication. In addition, we show that our scheme is resilient to memory-based Denial of Service (DOS) attack which occurs when an attacker floods the memory of a receiver with invalid messages. A security proof shows that HCBS-CPPA is secure in the random oracle. Regarding the simulation of our scheme, it turns out that HCBS-CPPA has the best performance when compared with several existing certificateless schemes. Additionally, it requires less execution time during the signing and verification process, as well as less communication overhead when compared to the existing schemes.

BPA: A Novel Blockchain-Based Privacy-Preserving Authentication Scheme for the Internet of Vehicles

The Internet of Vehicles (IoV) connects an isolated individual on the road to share information, which can improve traffic efficiency. However, the promotion of information sharing brings the critical security issues of identity authentication, followed by privacy protection issues in the authentication process in the IoV. In this study, we designed a blockchain-based conditional privacy-preserving authentication scheme for the IoV (BPA). Our scheme implements zero-knowledge proof (ZKP) to verify the identities of vehicles, which moves the authentication process down to the Roadside Units (RSUs) and achieves decentralized authentication at the edge nodes. Moreover, blockchain technology is utilized to synchronize a consistent ledger across all RSUs for recording and disseminating vehicle authentication states, which enhances the overall authentication process efficiency. We provide a theoretical analysis asserting that the BPA ensures enhanced security and effectively protects the privacy of all participating vehicles. Experimental evaluations confirm that our scheme outperforms existing solutions in terms of the computational and communication overhead.

Multi-TA model-based conditional privacy-preserving authentication protocol for fog-enabled VANET

The rapid growth of Vehicular Ad-hoc Networks (VANET), fueled by advancements in the Internet-of-Things, cloud computing, Intelligent Transportation Systems, and fog computing, has led to the introduction of fog node-based VANET to serve resource-constrained devices. In the traditional security models of VANET, due to the use of a centralized trusted authority, there is a chance of single-point-of-failure and service unavailable with the increased service access requests. Also, there was one-to-one communication between each roadside unit and trusted authority. This may increase the system complexity and increase the traffic load. To address these issues, a novel authentication protocol for fog-enabled VANET based on multiple trusted authority model is discussed which reduces the chance of service unavailability and single-point-of-failure as the entire traffic load is distributed among multiple sub-trusted authority. Due to the incorporation of fog node, a group of roadside units can be controlled centrally, where trusted authority does not need to perform individual authentication for each roadside unit. The proposed protocol's security is rigorously examined through both informal and formal security analysis. Additionally, the protocol exhibits enhanced security features, as demonstrated in a performance comparison section, showcasing its ability to meet the security and privacy requirements while incurring relatively low communication and computation and storage costs. Thus, the proposed protocol offers a secure and efficient authentication protocol for fog-enabled VANET.

Shared group session key-based conditional privacy-preserving authentication protocol for VANETs

Vehicular Ad-Hoc Networks (VANETs) have significantly enhanced driving safety and comfort by leveraging vehicular wireless communication technology. Due to the open nature of VANETs, conditional privacy-preserving authentication protocol should be offered against potential attacks. Efficient and secure authentication among vehicles in VANETs are important requirements, but there are various limitations in the existing conditional privacy-preserving authentication protocols for securing VANETs. To cope with the inherent issues, we propose a conditional privacy-preserving authentication protocol based share group session key (SGSK) by integrating the self-healing key distribution technique, blockchain, and MTI/C0 protocol. In our protocol, we use SGSK instead of the time-consuming Certificate Revocation List (CRL) checking, and we revoke malicious vehicles by updating SGSK. It is shared among unrevoked vehicles within a domain and across-domain. As a result, when a malicious revoked vehicle enters a new domain, it is difficult for it to access the system and send false messages. Furthermore, our protocol can not only achieve computation efficiency by reducing the number of computing operations of bilinear pairing but also resist various attacks while keeping conditional privacy protection. We implement our protocol in the Hyperledger Fabric platform. The experimental results show that our protocol is available to revoke 180 malicious vehicles in across-domain scenarios within one second, and it can meet the requirement of verifying 600 messages per second easily. Moreover, our comprehensive performance evaluations demonstrates that our protocol outperforms other approaches in terms of vehicle revocation checking cost, computation overhead, and communication overhead. In addition, to show the feasibility and validity of our protocol, we use SUMO and NS2 to simulate the actual VANET scenario and validate the efficiency and performance of our protocol. Simulation results prove the practicability of our protocol for VANETs.

An efficient and certificateless conditional privacy-preserving authentication and key agreement scheme for smart healthcare

Smart healthcare overcomes the limitations of time and space, allowing users to access medical and health services anywhere and anytime, thus improving the quality and efficiency of these services. However, due to its excessive reliance on wireless public networks, smart healthcare faces challenges and issues related to communication security. As a result, authentication and key agreement are critical as the first line of defense for smart healthcare communications. Over the past few years, numerous authentication and key agreement schemes have been proposed by experts and scholars, but most of these schemes are not applicable to practical scenarios due to their lack of security and efficiency. To address these issues, we propose an elliptic curve-based certificateless conditional privacy-preserving authentication and key agreement scheme. This scheme does not require endorsement from a Certificate Authority (CA) and features lightweight and secure properties, making it suitable for resource-limited smart healthcare communication. In addition, the security of the proposed scheme is proven under the random oracle model, and its safety is supplemented using BAN logic. Finally, performance analysis reveals that the proposed scheme not only satisfies security property and can withstand general attacks but also offers certain advantages in communication efficiency.

An Enhancement of Identity Based Conditional Privacy-preserving Authentication Process in Vehicular Ad Hoc Networks

In general, Vehicular Ad hoc Networks (VANETs) are permitting the communication between one vehicle with neighboring vehicles, infrastructure, and Road-Side Unit (RSU). In this, vehicle platoon is commonly known as the vehicle driving pattern it categorizes the batching of the vehicle in the on the trot fashion. It has been reviewed as an effective resolution to mitigate the reduction in traffic blockage and to widen the opulence of the travel. However, the malicious activities of any unauthorized person in VANET are increased the damage to authorized vehicles. In this manuscript, the Identity based Conditional Privacy-Preserving Authentication (ID-CPPA) signature scheme is proposed to detect the malignant command vehicle very efficiently by the consumer vehicle. In this, the proposed ID-CPPA method uses one-way hash functions for improving the efficiency of Road-Side Unit (RSU) signing and verification of a messages. In order to provide better concealment to the vehicle, Phase Truncated Fourier Transform based asymmetric encryption algorithm (PTFT-AE) is proposed. Thus, the proposed ID-CPPA-PTFT-AE approach has achieved 28.96%, 37.58%, 31.36% higher security rate and 25.8%, 37.9%, 42.6% lower delay than the existing MPDC-LPNS, PPSR-GS, and WCAA-TST methods respectively.

Cryptanalysis of Two Conditional Privacy Preserving Authentication Schemes for Vehicular Ad Hoc Networks

Conditional Privacy Preserving Authentication (CPPA) schemes are an effective way of securing communications in vehicular ad hoc networks (VANETs), as well as ensuring user privacy and accountability. Cryptanalysis plays a crucial role in pointing out the vulnerabilities in existing schemes to enable the development of more resilient ones. In 2019, Zhang proposed a CPPA scheme for VANET security (PA-CRT), based on identity batch verification (IBV) and Chinese Remainder Theorem (CRT). In this paper, we cryptanalyze Zhang’s scheme and point out its vulnerability to impersonation and repudiation attacks. In 2023, Zhang’s scheme was cryptanalyzed by Tao; however, we point out flaws in Tao’s cryptanalysis due to invalid assumptions; hence, we propose countermeasures to Tao’s attacks. Furthermore, in 2021, Xiong proposed a Certificateless Aggregate Signature (CLAS) scheme which is also cryptanalyzed in this paper. Finally, we analyze the causes and countermeasures by pointing out the vulnerabilities in each scheme that enabled us to launch successful attacks and proposing changes that would fortify these schemes against similar attacks in the future.

Hardware Secure Module Based Lightweight Conditional Privacy-Preserving Authentication for VANETs

Hardware Secure Module Based Lightweight Conditional Privacy-Preserving Authentication for VANETs

LRCPA: Lattice-Based Robust and Conditional Privacy-Preserving Authentication for VANETs

LRCPA: Lattice-Based Robust and Conditional Privacy-Preserving Authentication for VANETs

BTC2PA: A Blockchain-Assisted Trust Computation With Conditional Privacy-Preserving Authentication for Connected Vehicles

BTC2PA: A Blockchain-Assisted Trust Computation With Conditional Privacy-Preserving Authentication for Connected Vehicles

L-CPPA: Lattice-based conditional privacy-preserving authentication scheme for fog computing with 5G-enabled vehicular system.

The role that vehicular fog computing based on the Fifth Generation (5G) can play in improving traffic management and motorist safety is growing quickly. The use of wireless technology within a vehicle raises issues of confidentiality and safety. Such concerns are optimal targets for conditional privacy-preserving authentication (CPPA) methods. However, current CPPA-based systems face a challenge when subjected to attacks from quantum computers. Because of the need for security and anti-piracy features in fog computing when using a 5G-enabled vehicle system, the L-CPPA scheme is proposed in this article. Using a fog server, secret keys are generated and transmitted to each registered car via a 5G-Base Station (5G-BS) in the proposed L-CPPA system. In the proposed L-CPPA method, the trusted authority, rather than the vehicle's Onboard Unit (OBU), stores the vehicle's master secret data to each fog server. Finally, the computation cost of the suggested L-CPPA system regards message signing, single verification and batch verification is 694.161 ms, 60.118 ms, and 1348.218 ms, respectively. Meanwhile, the communication cost is 7757 bytes.

Conditional privacy-preserving authentication scheme for V2V communication without pseudonyms

Pseudonym is widely used in conditional privacy-preserving authentication (CPPA) scheme for vehicle-to-vehicle (V2V) communication in vehicular ad hoc networks (VANETs) in order to protect user’s privacy. The main disadvantage of pseudonym-based CPPA schemes is that the pseudonym has to be frequently updated, which puts a heavy burden on VANETs, due to linkage-attack. To solve this problem, we proposed a CPPA scheme for V2V communication without involving pseudonyms. The vehicle does not use any pseudonym in the proposed scheme, therefore it is immune to pseudonym updating and management problems. Moreover, the scheme enables secure V2V communication, which means that only legal vehicles have access to the transmitted messages. Security analysis shows that the scheme supports secure properties of anonymity, unlinkability, non-repudiation, message integrity, traceability, and revocation. Performance analysis and extensive simulations show that the scheme is computationally efficient and has the lowest average message delay among compared schemes.

A Security-Enhanced Certificateless Conditional Privacy-Preserving Authentication Scheme for Vehicular Ad Hoc Networks

By adopting advanced Internet of Things (IoT) technology to sense and collect traffic-related information to improve traffic safety and efficiency, the vehicular ad hoc network (VANET) is becoming a prominent application that changes human driving experiences in the current era. Because frequent data exchange occurs in open environments, VANETs are inherently vulnerable to security and privacy attacks. In history, many certificateless aggregate signature (CLAS) schemes with conditional privacy-preserving (CPP) have been proposed to ensure the authenticity and integrity of the exchanged data and protect users’ privacy. However, we reveal that the state-of-the-art schemes cannot be deployed in practical VANET applications by proposing concrete signature forgery attacks. To this end, we propose a new CLAS-based authentication scheme with CPP for VANETs. The rigorous security proofs based on the standard cryptographic assumption show that the scheme has enhanced security. Moreover, theoretical analysis and experimental evaluation illustrate the practicality of our design.

Efficient Conditional Privacy-Preserving Authentication Scheme for Safety Warning System in Edge-Assisted Internet of Things

With the advent of smart cities, the significance of the Internet of Things (IoT) is gaining greater prominence. At the same time, the safety early warning system in the IoT has a significant impact on real-time monitoring and the response to potential risks. Despite the advancements made in edge-assisted IoT deployments, several challenges and constraints persist. Given the potential threat to life posed by safety-related messages, ensuring the authenticity of messages in the edge-assisted IoT safety warning system is crucial. However, considering the identity privacy of devices participating in the edge-assisted Internet of Things system, directly verifying the identity of the sending device is undesirable. To address this issue, in this work, we design a linkable group signature scheme that allows devices to anonymously send safety-related messages to edge nodes, defending against Sybil attacks while ensuring the traceability of malicious device identities. Then, we present a high-efficiency conditional privacy-preserving authentication (CPPA) scheme based on the designed group signatures for the safety warning system in edge-assisted IoT. This scheme effectively protects device identity privacy while providing a reliable authentication mechanism to ensure the credibility and traceability of alert messages. The proposed scheme contributes to the field of safety warning systems in the context of edge-assisted IoT, providing a robust solution for privacy preservation and authentication.