Invalid Signatures Research Articles

Efficient Authentication Steps for Vehicle Transmission in Ad-Hoc Networks

Vehicular ad-hoc networks (VANETs) are underactive development, thanks in part to recent advances in wireless communication and networking technologies. The most fundamental part of VANET is to enable message authentications between vehicles and roadside units. Message authentication using proxy vehicles has been proposed to reduce the computational overhead of roadside units significantly. In this message authentication scheme, a proxy vehicle that verifies multiple messages at the same time improves roadside units’ efficiency. In this paper first, we show that the only proxy-based authentication scheme (PBAS) presented for this goal by Liu et al. cannot guarantee message authenticity and also it is not resistant to impersonation and modification attacks and false acceptance of batched invalid signatures. Next, we propose a new identity-based message authentication scheme using proxy vehicles (ID-MAP). Then guarantee that it can satisfy the message authentication requirements, existential unforgeability of underlying signatures against adaptability chosen message, and identity attack is proved under the Elliptic Curve discrete logarithm problem (ECDLP) in the random oracle model. It should be highlighted that ID MAP not only is more efficient than PBAS since it is pairing-free and identity based and also it does not use map-to-point hash functions, also, it satisfies the security and privacy requirements of VANETs. Furthermore, analysis shows that the required time to verify 3000 messages in ID-MAP is reduced by 76% compared to that PBAS.

DRCLAS: An efficient certificateless aggregate signature scheme with dynamic revocation in vehicular ad-hoc networks

The emergence of the Vehicular Ad-hoc Networks (VANETs) has greatly enhanced the efficiency and safety of transportation systems. However, due to the dynamicness and openness of vehicular networks, it is vulnerable for VANETs to confront various security threats. The dissemination of disinformation and the occurrence of attacks within these networks can result in severe damage and compromise the overall security of transportation systems. To mitigate such challenges, this paper presents an efficient certificateless aggregate signature scheme with dynamic revocation in VANETs. Taking use of the early-stopping factorial bitwise divisions (EFBD) algorithm, it achieves the invalid signatures tracking, and revokes the malicious vehicles dynamically. In addition, by combining the fingerprint counting bloom filter (FP-CBF), the trust assessment mechanism and the cloud server, it enables the vehicle to remedy its incorrect signatures. At last, through the comprehensive security and performance analysis, it demonstrates that this protocol enjoys improved communication security and computational efficiency.

Examining causes of disputes in subcontracting litigation cases using text mining and natural language processing techniques

Disputes are common and widespread in subcontracting practices and would ultimately lead to litigation resulting in significant negative consequences including delay, increased cost, and tarnished reputation of contracting parties. Although considerable studies have analyzed disputes in construction projects, research efforts still fall short in investigating causes of disputes in subcontracting practices. To bridge the knowledge gap, this paper investigated the causes of disputes in subcontracting practices by automatically examining 3150 litigation cases that are publicly available in China using text mining and NLP (natural language processing) techniques. Documents of litigation cases were presented into vectors by data preprocessing and vector presentation. Clustering analysis of the data was conducted by using an improved K-Means model, K-Means++. Finally, 37 causes of disputes were discovered in the subcontracting litigation cases. Results showed that variations due to unforeseen circumstances, labor service issues from subcontractors, disagreement on engineering quantities between subcontractors and other contracting parties, invalid signature of subcontractors for obtaining more payment, payment issues between subcontractors and clients or general contractors, contradictory on the return of performance bond, disagreement on the interest of late payment, and arrears issues suffered by subcontractors were the top eight significant causes of disputes in subcontracting practices in China. This study contributes by systematically exploring the causes of disputes in subcontracting practices using automated text analysis approaches instead of manual content analysis. The findings of this study can provide construction practitioners a deeper understanding of disputes in subcontracting and thereby helping them increase their capacity to handle disputes.

Fault-Tolerant Aggregate Signature Schemes against Bandwidth Consumption Attack

A fault-tolerant aggregate signature (FT-AS) scheme is a variant of an aggregate signature scheme with the additional functionality to trace signers that create invalid signatures in case an aggregate signature is invalid. Several FT-AS schemes have been proposed so far, and some of them trace such rogue signers in multi-rounds, i.e., the setting where the signers repeatedly send their individual signatures. However, it has been overlooked that there exists a potential attack on the efficiency of bandwidth consumption in a multi-round FT-AS scheme. Since one of the merits of aggregate signature schemes is the efficiency of bandwidth consumption, such an attack might be critical for multi-round FT-AS schemes. In this paper, we propose a new multi-round FT-AS scheme that is tolerant of such an attack. We implement our scheme and experimentally show that it is more efficient than the existing multi-round FT-AS scheme if rogue signers randomly create invalid signatures with low probability, which for example captures spontaneous failures of devices in IoT systems.

Heterogeneous Fault-Tolerant Aggregate Signcryption with Equality Test for Vehicular Sensor Networks

The vehicular sensor network (VSN) is an important part of intelligent transportation, which is used for real-time detection and operation control of vehicles and real-time transmission of data and information. In the environment of VSN, massive private data generated by vehicles are transmitted in open channels and used by other vehicle users, so it is crucial to maintain high transmission efficiency and high confidentiality of data. To deal with this problem, in this paper, we propose a heterogeneous fault-tolerant aggregate signcryption scheme with an equality test (HFTAS-ET). The scheme combines fault-tolerant and aggregate signcryption, which not only makes up for the deficiency of low security of aggregate signature, but also makes up for the deficiency that aggregate signcryption cannot tolerate invalid signature. The scheme supports one verification pass when all signcryptions are valid, and it supports unbounded aggregation when the total number of signcryptions grows dynamically. In addition, this scheme supports heterogeneous equality test, and realizes the access control of private data in different cryptographic environments, so as to achieve flexibility in the application of our scheme and realize the function of quick search of plaintext or ciphertext. Then, the security of HFTAS-ET is demonstrated by strict theoretical analysis. Finally, we conduct strict and standardized experimental operation and performance evaluation, which shows that the scheme has better performance.

Aggregate Signature Schemes with Traceability of Devices Dynamically Generating Invalid Signatures

Aggregate Signature Schemes with Traceability of Devices Dynamically Generating Invalid Signatures

A trust-aware cluster-based communication architecture for vehicular named data networking

Information-centric Networking (ICN) is a new networking paradigm that aims to solve the problem of the traditional TCP/IP-based Internet. Content-centric Networking (CCN) and Named Data Networking (NDN), both based on the Interest/Data communication paradigm, are two of the most well-known and specialized implementations of ICN. In contrast to typical networks, NDN enables intrinsic security, which ensures data security rather than communication channel security. Each response/data packet in transit has a signature on the contents of the data to ensure security. As a result, an invalid signature indicates an unauthenticated data packet. This ongoing hierarchical authentication verification approach causes a significant delay while providing the appropriate security levels. As a result, in a highly mobile environment with delay-sensitive applications like Vehicular Ad hoc Networks (VANETs), such a technique is neither viable nor scalable. We present a unique Trust-Aware Cluster-based Communication Architecture (TACCA) for Vehicular Named Data Networking in this study, which aims to improve the security of NDN-driven VANETs (VNDN). It separates the route segments into clusters and chooses cluster heads based on their trustworthiness and proximity to the center location. The selected cluster heads are then in charge of disseminating interest packets to prevent the broadcast storm problem. Once the data producer has been located, the data is returned to the requester in the quickest and most secure manner possible. Simultaneously, the intermediate vehicles decided whether or not to verify the data's validity based on their subjective perceptions of the data's producer's conduct. As a result, the calculation complexity and time are reduced. Our idea is able to maintain vanilla NDN security standards while lowering the produced end-to-end latency by more than three times, according to simulation data. As a result, the proposed TACCA is more suited to mobile networks(...)

On the Design of Blockchain-Based ECDSA With Fault-Tolerant Batch Verification Protocol for Blockchain-Enabled IoMT.

The blockchain-enabled internet of medical things (IoMT) is an emerging paradigm that could provide strong trust establishment and ensure the traceability of data sharing in the IoMT networks. One of the fundamental building blocks for Blockchain is Elliptic Curve Digital Signature Algorithm (ECDSA). Nevertheless, when processing a large number of transactions, the verification of multiple signatures will incur cumbersome overhead to the nodes in Blockchain. Although batch verification is able to provide a promising approach that verifies multiple signatures simultaneously and efficiently, the upper bound of batch size is limited to small-scale and the efficiency will drop rapidly as the batch size grows in the state-of-the-art ECDSA batch schemes. Meanwhile, most of the existing researches only focus on improving the efficiency of batch verification algorithms in various cryptosystem while ignoring the identification of invalid signatures, which could cause severe performance degradation when the batch verification fails. Motivated by these observations, this paper proposes an efficient and large-scale batch verification scheme with group testing technology based on ECDSA. The application of the presented protocols in Bitcoin and Hyperledger Fabric has been analyzed as supportive and effective. When the batch verification returns a false result, we utilize group testing technology to improve the efficiency of identifying invalid signatures. Comprehensive simulation results demonstrate that our protocol outperforms the related ECDSA batch verification schemes.

CLASRM: A Lightweight and Secure Certificateless Aggregate Signature Scheme with Revocation Mechanism for 5G-Enabled Vehicular Networks

The rapid deployment of 5G technology has further strengthened the large-scale interconnection between sensing devices and systems and promoted the rapid development of smart cities and intelligent transportation systems. 5G-enabled vehicular networks take advantage of cellular vehicle-to-everything (C-V2X) technology to achieve the connection between moving vehicles, between vehicles and infrastructure, and between vehicles and the cloud, which can reduce the possibility of traffic jams and accidents, improve transportation efficiency, and realize automatic driving. Besides, 5G-enabled vehicular networks also provide infotainment services and industry application services. High-strength data transmission, however, will bring a serious burden of resource overhead, and there are hidden dangers of security and privacy in the communication process of vehicular networks. Some current vehicular network authentication schemes adopt public key infrastructure-based (PKI-based) and identity-based authentication methods to achieve conditional privacy preservation. Still, these schemes are too expensive and cannot address the problems of costly certificate management or risky key escrow. Some schemes use computationally complex bilinear pairing operations that result in low efficiency and do not consider the revocation of malicious nodes so that they cannot effectively prevent further malicious attacks. This paper proposes a lightweight certificateless aggregate signature (CLAS) scheme with a revocation mechanism suitable for 5G-enabled vehicular networks in response to the above problems. Our proposed scheme uses aggregation signature technology to aggregate multiple signatures into a single short signature, thus reducing communication overhead and storage overhead of road side units (RSUs). Furthermore, our proposed scheme utilizes the elliptic curve cryptography (ECC) to reduce verification time and computational overhead. Moreover, in order to prevent malicious users from sending invalid signatures to attack, our proposed scheme uses binary search to identify invalid signatures and introduces a cuckoo filter to revoke malicious users to prevent reattack. Finally, formal proof and experimental analysis show that our proposed scheme has greater advantages with respect to security and efficiency compared with the previous schemes.

Secure server-aided attribute-based signature with perfect anonymity for cloud-assisted systems

Attribute-based signature (ABS) is an attractive cryptographic primitive, but it is unsuitable for resource-constrained scenarios because of its high computational cost. Server-Aided Attribute-Based Signature (SAABS) was introduced to overcome this shortcoming by using cloud computing technology. In this paper, we perform cryptanalysis on Xiong et al. (2020) and Cui et al. (2018). We show that Xiong et al.’s scheme is incorrect and forgeable. Neither of these two schemes achieves anonymity. In both schemes, an adversary can collude with the server to replace the attribute set and make the verifier accept an invalid signature. Our attacks imply that the previous definitions of unforgeability and anonymity are not conforming to the actual cloud-assisted scenarios. Then, we present more accurate security models for SAABS. We define a stronger definition for unforgeability, a stronger notion called perfect anonymity, and a new notion called server-aided verification security. Finally, we propose a new idea to prevent the server from attacking anonymity and an improved scheme to fix our attacks. Our scheme achieves all the security properties, supports expressive access structure, reduces the computational overhead to a low level, and is especially suitable for cloud-assisted systems.

Efficient Small-Batch Verification and Identification Scheme With Invalid Signatures in VANETs

Vehicular Ad hoc networks (VANETs) plays an important role in reducing casualties, optimizing traffic distribution and improving traffic efficiency. Nevertheless, with the rapid growth of vehicles, the existing VANETs computing capacity will not be able to guarantee the service quality due to inefficient signature verification and identification. In this paper a small-batch verification and identification scheme is presented to speed up the signature verification and the invalid signature identification. In the proposed scheme, according to the signature number and the historical signature error rate, we first build an optimization model, which transforms the problem how to divide a batch of signatures into several appropriate small-batches into an integer programming problem, and then stores the optimal batch solution table in roadside units (RSUs). Moreover, in view of the current task, RSU can automatically divide a batch of signatures into several appropriate small-batches. After then, any invalid signature in these small-batches can be quickly identified by using of the exponentiation method. Finally, by comparison with the existing schemes, the total time delay is reduced to 50% in optimal circumstances. Simulation results show that the proposed scheme can achieve fast signature verification and invalid signature identification.

Efficient Privacy-Preserving Authentication Scheme With Fine-Grained Error Location for Cloud-Based VANET

As an emerging technology, cloud-based Vehicular Ad-Hoc Network (VANET) can significantly improve the efficiency of transportation systems by alleviating traffic congestion and optimizing resource management. However, since the information transmitted in VANET is distributed in an open-access environment, security and privacy are now becoming vital concerns, especially when attackers own more and more resources. Recently, many tamper-proof devices (TPD)-based authentication schemes have been proposed to tackle the above-mentioned challenges, while most of them are dependent on ideal TPDs with very strong security assumptions. Moreover, when the aggregate signature verification fails, these schemes can do nothing but discard the aggregate signature completely, which makes them impractical in VANET. To address the above concerns, we propose a more realistic TPD-based authentication scheme with privacy-preserving features for cloud-based VANET. Specifically, the off-line self-updating method is utilized to update the data in TPD periodically to resist side-channel attacks. Furthermore, an efficient fine-grained error location algorithm is designed to quickly detect all invalid signatures within a problematic aggregate signature scenario. Our performance analysis shows that the proposed scheme outperforms the existing ones in terms of security, computation delay and communication overhead, thus more suitable in practical cloud-based VANET environment.

Invalid Signatures Searching Bitwise Divisions-Based Algorithm for Vehicular Ad-Hoc Networks

Vehicular ad-hoc networks (VANETs) are the crucial part of intelligent transportation systems (ITS), which are brought to enhance the security, efficiency, and comfort of transportation. VANETs have aroused extensive attention in the world recently. One of the challenges in practice is real time and low delay, which strongly requires VANETs to be efficient. Existing schemes have properly solved the problem which is how to aggregate the signatures and verify the aggregated signature. However, few solutions are proposed to pinpoint all invalid signatures if existing. The algorithms that can find all invalid signatures are not efficient enough. Following consideration of the above deficiencies of existing approaches, this paper proposes a factorial bitwise divisions (FBD) algorithm and its optimized version and early-stopping factorial bitwise divisions (EFBD) algorithm. Both algorithms are parallel-friendly. Compared with the binary-based batch verification algorithm, the experimental results demonstrate that the proposed algorithms achieve better performance in both theory and practice at low invalid signatures’ rate. Especially, in the parallel condition, when the number of invalid signatures is 1, the proposed algorithms cost only one aggregation-verification delay, while the comparison is more than log 2 n times.

Bitwise Division Searching Algorithm for VANETs

Vehicular ad-hoc networks (VANETs) are the key technology supporting the intelligent transportation system (ITS), which is composed of vehicle nodes with wireless communication capability and roadside infrastructures. One of the obstacles is how to use batch verification to verify signatures simultaneously. To solve the problem of low verification efficiency in VANETs. This paper defines the problem and proposes an early-stopping factorial bitwise divisions (EFBD) algorithm. The proposed parallel-friendly algorithm achieves better performance in both theory and practice at low invalid signatures rate. Especially, in the parallel condition, the proposed algorithm costs only one aggregation-verification delay when the number of invalid signatures is 1.

A Novel Efficient Certificateless Signature Scheme for the Prevention of Content Poisoning Attack in Named Data Networking-Based Internet of Things

Recently, Named Data Networking (NDN) has emerged as a popular and active Internet architecture that addresses the issues of current host-centric communication. NDN is well suited for Internet of Things (IoT) which possesses massive applications that dominate the Internet today. It intends to provide named-based routing, in-networking caching, built-in mobility and multicast support as part of its design which leads to a substantial improvement in content delivery/retrieval. Though, this new architecture aches from some new challenges in terms of security. In this article, we seek our attention towards Content Poisoning Attack (CPA). The purpose of CPA is to inject poisoned content with an invalid signature into the NDN-based IoT networks. Unfortunately, none of the existing proposals work effectively when malicious attackers compromise the caches of NDN routers. To prevent this, we proposed a certificateless signature scheme for the preservation of CPA in NDN-based IoT networks. The proposed scheme is formally secure under the security hardness of Hyperelliptic Curve Discrete Logarithm Problem (HCDLP) with a security simulation/validation in “Automated Validation of Internet Security Protocols and Applications (AVISPA).” Besides, the formal proof we also compared the designed scheme with some existing solutions to show the cost-efficiency in terms of communication overhead and computation cost. To conclude, a robust deployment on NDN-based IoT networks is shown.

Nested cover-free families for unbounded fault-tolerant aggregate signatures

Aggregate signatures are used to create one short proof of authenticity and integrity from a set of digital signatures. However, one invalid signature in the set invalidates the entire aggregate, giving no information on which signatures are valid. Hartung et al. (2016) [6] propose a fault-tolerant aggregate signature scheme based on combinatorial group testing. Given a bound d on the number of invalid signatures among n signatures to be aggregated, this scheme uses d-cover-free families to determine which signatures are invalid. These combinatorial structures guarantee a moderate increase on the size of the aggregate signature that can reach the best possible compression ratio of O(nlog⁡n), for fixed d, coming from an information theoretical bound. The case where the total number of signatures grows dynamically (unbounded scheme) was not satisfactorily solved in their original paper, since explicit constructions had constant compression ratios. In the present paper, we propose efficient solutions for the unbounded scheme, relying on sequences of d-cover-free families that we call nested families. Some of our constructions yield high compression ratio close to the best known upper bound. We also propose the use of (d,λ)-cover-free families to support the loss of up to λ−1 parts of the aggregate.

A secure and efficient certificateless batch verification scheme with invalid signature identification for the internet of things

With the continuously developing wireless communication technique, the Internet of Things (IoT) has been deployed in various domains. In the IoT, numerous smart devices exchange information transparently and seamlessly via the open channel to provide intelligent and convenient services for the citizens. Due to the vulnerable nature of the communication channel, ensuring data authenticity of the transmitted information is a challenging issue. Certificateless signature (CLS) is regarded as an appropriate cryptographical primitive to protect data authenticity in the IoT. However, the existing CLS schemes are infeasible for the practical IoT systems, since individual verification causes network congestion and service delay in the face of massive service requests. To improve the verification efficiency, plenty of CLS schemes with batch verification have been investigated to verify multiple signatures quickly at once. Despite the improvement of verification efficiency, these schemes have poor efficiency or security issue. Furthermore, the batch verification failure cannot be settled in these schemes, which reduces the advantage of batch verification significantly. Motivated by the above problems, this paper presents a secure and efficient CLS scheme with batch verification and invalid signature identification. The proposed scheme is provably secure under the random oracle model. The comprehensive comparison analysis demonstrates that the presented scheme is superior to the related works in security and performance.

A Lightweight Identity-Based Signature Scheme for Mitigation of Content Poisoning Attack in Named Data Networking With Internet of Things

Named Data Networking (NDN) is one of the future envisioned networking paradigm used to provide fast and efficient content dissemination with interest-based content retrieval, name-based routing and in-network content caching. On the one hand, this new breed of future Internet architecture is becoming a key technology for data dissemination in the IoT networks; on the other hand, NDN suffers from new challenges in terms of data security. Among them, a content poisoning attack is the most common data security challenge. The aim of this attack is to inject poisoned content with an invalid signature to the network. Therefore, to prevent NDN against possible content poisoning attack, a signature of the contents is appended to each data packet for verifications. In this paper, we propose an identity-based signature scheme for IoT-based NDN networks, with a special emphasis on content integrity and authenticity. The proposed scheme is based on the concept of the Hyperelliptic curves, which provide the same level of security as Rivest-Shamir-Adleman (RSA), Bilinear pairing and Elliptic Curve Cryptosystems (ECC) with lower-key size. The proposed scheme is subject to both formal and informal security analysis in order to show the feasibility of our scheme. Finally, the performance of the proposed scheme is analyzed via comparison with the relevant existing schemes that authenticates the superiority of our scheme in terms of security and efficiency.

Cipher Text Policy Attribute Based Encryption (Cp-Abe) using Concealed Policy in Public Cloud

Cloud computing focus on the data storage and the management. Since the cloud is open source for the user there have to protect the privacy and the security of the data which are less maintenances. There are several approaches designed to establish a secure data. The Signature work of this scheme is to allow the user to verify the shared in the cloud using the secret key. The anonymzed access policy can be viewed by the Cloud Service Provider (CSP) and the user; hence the recipient information will not be leaked or disclosed. The novel idea of this method is to conserve the privacy of the access policy using Cipher text Policy Access Based Encryption (CP- ABE) scheme. We have proposed a novel system, “Concealed Policy using mandatory and Role based”, using time elapsed of 10 secs. Within the required time the user, should response to the cloud using their Secret key(SK) to decrypt the file, and the owners with the Public key (PK), must encrypt the file using the mandatory access and upload it to the Third Party Auditor (TPA).This will improves the security to the user in the cloud environment. The concealed policy relies on two stages, there is Mandatory policy and Role based policy using the signature verification. Which are more efficient to the user to encrypt and decrypt the file. Without verification of the signature, the legitimate user cannot access the particulars in the cloud environment. If the signature of the user is valid, there can access (decrypt) the file using the SK. whereas, invalid signature occurs the TPA (Third Party Auditor) traces the reasonable user responsible for the signature and check with the mandatory access to encrypt the file, Nether less the access den ailed.

A Secure and Efficient Authentication Technique for Vehicular Ad-Hoc Networks

Vehicular ad-hoc networks (VANETs) are under active development, thanks in part to recent advances in wireless communication and networking technologies. The most fundamental part in VANETs is to enable message authentications between vehicles and roadside units. Message authentication using proxy vehicles has been proposed to reduce the computational overhead of roadside units significantly. In this message authentication scheme, proxy vehicles that verify multiple messages at the same time improve roadside units’ efficiency. In this paper, first we show that the only proxy-based authentication scheme (PBAS) presented for this goal by Liu et al. cannot guarantee message authenticity, and also it is not resistant against impersonation and modification attacks and false acceptance of batched invalid signatures. Next, we propose a new identity-based message authentication scheme using proxy vehicles (ID-MAP). Then, to guarantee that it can satisfy the message authentication requirement, existential unforgeability of underlying signature against adaptively chosen-message and identity attack is proved under elliptic curve discrete logarithm problem in the random oracle model. It should be highlighted that ID-MAP not only is more efficient than PBAS since it is pairing-free and identity-based, and also it does not use map-to-point hash functions, but also it satisfies security and privacy requirements of VANETs. Furthermore, analysis shows that the required time to verify 3000 messages in ID-MAP is reduced by 76% compared to that of PBAS.