A quantum blind signature scheme based on dense coding for non-entangled states

In some schemes, quantum blind signatures require the use of difficult-to-prepare multiparticle entangled states. By considering the communication overhead, quantum operation complexity, verification efficiency and other relevant factors in practical situations, this article proposes a non-entangled quantum blind signature scheme based on dense encoding. The information owner utilizes dense encoding and hash functions to blind the information while reducing the use of quantum resources. After receiving particles, the signer encrypts the message using a one-way function and performs a Hadamard gate operation on the selected single photon to generate the signature. Then the verifier performs a Hadamard gate inverse operation on the signature and combines it with the encoding rules to restore the message and complete the verification.Compared with some typical quantum blind signature protocols, this protocol has strong blindness in privacy protection,and higher flexibility in scalability and application. The signer can adjust the signature operation according to the actual situation, which greatly simplifies the complexity of the signature. By simultaneously utilizing the secondary distribution and rearrangement of non-entangled quantum states, a non-entangled quantum state representation of three bits of classical information is achieved, reducing the use of a large amount of quantum resources and lowering implementation costs. This improves both signature verification efficiency and communication efficiency while, at the same time, this scheme meets the requirements of unforgeability, non-repudiation, and prevention of information leakage.

Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform

This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement techniques.The QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding phase.This innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely implemented.Unlike existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation process.To assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud platform.The results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind signatures.Furthermore,we have established authentic security thresholds(82.102%)in the presence of real noise,thereby emphasizing the practicality of our proposed solution.

Identity-Based Blind Signature from Lattices

Blind signature allows a user to get a signature of a signer on an arbitrary message,and the verifier can convince that the signature is indeed signed by the signer without leaking any information about the message.This property is necessary when the user’s privacy needs protection,such as a bank bill,a trade secret,etc.As an alternative of public key infrastructure,the identity-based system can simplify the key management procedures in certificate-based public key systems.Inspired by the requirement of identity-based blind signature in the post quantum world,we research on identity-based blind signature based on hard lattice problems under the random Oracle model.We propose a construction built upon the blind signature by Rückert,and it is proved to be one-more unforgeable against selective identity and chosen message attacks（s ID-CMA）and unconditionally blind.The proposed scheme has 2 moves,and its security can be reduced to the small integer solution（SIS）problem.

An Identity-Based Strong Designated Verifier Proxy Signature Scheme

In a strong designated verifier proxy signature scheme, a proxy signer can generate proxy signature on behalf of an original signer, but only the designated verifier can verify the validity of the proxy signature. In this paper, we first define the security requirements for strong designated verifier proxy signature schemes. And then we construct an identity-based strong designated verifier proxy signature scheme. We argue that the proposed scheme satisfies all of the security requirements.

An Improved Identity-Based Society Oriented Signature Scheme with Anonymous Signers

In this paper, we present an improved identity-based society oriented signature scheme with anonymous signers, which satisfies： （1） when members leave or join an organization, the public verification key and the signature verification procedure are unchanged; （2） a user participates in several organizations at the same time, her secret key is only related with her identity. However, no previous schemes have these two properties.

An Identity-Based Scheme of Fair Exchange of Digital Signatures

Fair exchange of digital signatures is an important tool for signing digital contracts, e-payment and other electronic commerce actions. An ID-based scheme of fair exchange of digital signature is proposed in this paper. The protocol relies on a trusted third party, but is ＂optimistic＂, in that the third party is only needed in cases where one player attempts to cheat or simply crashes. The proposed scheme has properties of short signature, low computation and verification cost. It can realize exchange of digital signatures fairly and effic, iently. A key feature of our scheme is that it is identity-based, which needs no certificates and has a simple key management. To our best knowledge, this is the first identity based scheme of fair exchange of digital signatures.

Improvement of Identity-Based Threshold Proxy Signature Scheme with Known Signers

In 2006, Bao et al proposed an identlty-based threshold proxy signature scheme with known signers. In this paper, we show that Bao et al＇s scheme is vulnerable to the forgery attack. An adversary can forge a valid threshold proxy signature for any message with knowing a previously valid threshold proxy signature. In addition, their scheme also suffers from the weakness that the proxy signers might change the threshold value. That is, the proxy signers can arbitrarily modify the threshold strategy without being detected by the original signer or verifiers, which might violate the original signer＇s intent. Furthermore, we propose an improved scheme that remedies the weaknesses of Bao et al＇s scheme. The improved scheme satisfies all secure requirements for threshold proxy signature.

A New ID-Based Proxy Blind Signature Scheme

An identity-based proxy blind signature scheme from bilinear pairings isintroduced, which combines the advantages of proxy signature and blind signature. Furthermore, ourscheme can prevent the original signer from generating the proxy blind signature, thus the profitsof the proxy signer are guaranteed. We introduce bilinear pairings to minimize computationaloverhead and to improve the related performance of our scheme. In addition, the proxy blindsignature presented is non-repudiable and it fulfills perfectly the security requirements of a proxyblind signature.

Efficient ID-Based Proxy Blind Signature Scheme

In a proxy blind signature scheme, the proxy signer is allowed to generate a blind signature on behalf of the original signer. The proxy blind signature scheme is useful in several applications such as e-voting and e-payment. In this paper, we propose an identity-based proxy blind signature scheme which combines the advantages of proxy signature and of blind signature. Our scheme fulfills peffecdy the security requirements of a proxy blind signature. Comparing the previous scheme, our scheme needs less computational overhead and is more efficient.

Fair quantum blind signatures

We present a new fair blind signature scheme based on the fundamental properties of quantum mechanics. In addition, we analyse the security of this scheme, and show that it is not possible to forge valid blind signatures. Moreover, comparisons between this scheme and public key blind signature schemes are also discussed.

A Proxy Blind Signature Scheme Based on DLP

A proxy signature scheme allows an original signer to delegate his signing capability to a proxy signer who can sign on behalf of the original signer. A blind signature is the concept with a salient feature that the signer can not make a linkage between the blind signature and the identity of the requester. Proxy signature and blind signature are used widely in electronic commerce. With satisfying the security properties of both two signatures, a new proxy blind signature scheme based on discrete logarithm problem is proposed.

A Fair Blind Signature Scheme to Revoke Malicious Vehicles in VANETs

With the rapid development of IoT(Internet of Things),VANETs(Vehicular Ad-Hoc Networks)have become an attractive ad-hoc network that brings convenience into people’s lives.Vehicles can be informed of the position,direction,speed and other real-time information of nearby vehicles to avoid traffic jams and accidents.However,VANET environments could be dangerous in the absence of security protection.Because of the openness and self-organization of VANETs,there are plenty of malicious pathways.To guarantee vehicle security,the research aims to provide an effective VANET security mechanism that can track malicious vehicles as necessary.Therefore,this work focuses on malicious vehicles and proposes an anonymous authentication scheme in VANETs based on the fair blind signature to protect vehicle security.

A Novel Post-Quantum Blind Signature for Log System in Blockchain

In recent decades, log system management has been widely studied fordata security management. System abnormalities or illegal operations can befound in time by analyzing the log and provide evidence for intrusions. In orderto ensure the integrity of the log in the current system, many researchers havedesigned it based on blockchain. However, the emerging blockchain is facing significant security challenges with the increment of quantum computers. An attackerequipped with a quantum computer can extract the user's private key from thepublic key to generate a forged signature, destroy the structure of the blockchain,and threaten the security of the log system. Thus, blind signature on the lattice inpost-quantum blockchain brings new security features for log systems. In ourpaper, to address these, firstly, we propose a novel log system based on post-quantum blockchain that can resist quantum computing attacks. Secondly, we utilize apost-quantum blind signature on the lattice to ensure both security and blindnessof log system, which makes the privacy of log information to a large extent.Lastly, we enhance the security level of lattice-based blind signature under therandom oracle model, and the signature size grows slowly compared with others.We also implement our protocol and conduct an extensive analysis to prove theideas. The results show that our scheme signature size edges up subtly comparedwith others with the improvement of security level.

A New Anti-Quantum Proxy Blind Signature for Blockchain-Enabled Internet of Things

Blockchain technology has become a research hotspot in recent years with the prominent characteristics as public,distributed and decentration.And blockchain-enabled internet of things(BIoT)has a tendency to make a revolutionary change for the internet of things(IoT)which requires distributed trustless consensus.However,the scalability and security issues become particularly important with the dramatically increasing number of IoT devices.Especially,with the development of quantum computing,many extant cryptographic algorithms applied in blockchain or BIoT systems are vulnerable to the quantum attacks.In this paper,an anti-quantum proxy blind signature scheme based on the lattice cryptography has been proposed,which can provide user anonymity and untraceability in the distributed applications of BIoT.Then,the security proof of the proposed scheme can derive that it is secure in random oracle model,and the efficiency analysis can indicate it is efficient than other similar literatures.

CERTIFICATELESS SIGNATURE AND BLIND SIGNATURE

Certificateless public key cryptography is a new paradigm introduced by Al-Riyami and Paterson.It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography(ID-PKC).Due to the advantages of the certificateless public key cryptography,a new efficient certificateless pairing-based signature scheme is presented,which has some advantages over previous constructions in computational cost.Based on this new signature scheme,a certificateless blind signature scheme is proposed.The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.

Cryptanalysis of fair quantum blind signatures

We investigate the fair quantum blind signature scheme proposed by Wang and Wen [Wang T Y and Wen Q Y 2010 Chin. Phys. B 19 060307], which uses the fundamental properties of quantum mechanics and the availability of a trusted arbitrator. However, in this paper, we find that the protocol cannot satisfy the property of non-forgeability even under the condition that the trusted arbitrator is totally credible. Moreover, a simple feasible suggestion for improving the protocol is proposed.

A THRESHOLD BLIND SIGNATURE FROM WEIL PAIRING ON ELLIPTIC CURVES

The idea behind a (t, n) threshold blind signature is that a user can ask at least t out of n players of a group to cooperate to generate a signature for a message without revealing its content. This paper first presents a new blind signature scheme from Weil pairing on elliptic curves. Based on this scheme, a threshold blind signature scheme is proposed. It is efficient and has the security properties of robustness and unforgeability. In the proposed scheme, the group manger is introduced to take the role of distributing the group secret key to each player. However, he cannot forge the players to generate partial blind signatures (Each partial blind signature depends on not only the secret key of the player, but also a random number the player picks). Compared with a threshold signature with a trusted third party, its advantage is obvious; Compared with a threshold signature without a trusted third party, it is more simple and efficient.

CONSTRUCTION OF PROXY BLIND SIGNATURE SCHEME BASED ON MULTI-LINEAR TRANSFORM

A general method of constructing proxy blind signature is proposed based on multilinear transform. Based on this method, the four proxy blind signature schemes are correspondently generated with four different signature equations, and each of them has four forms of variations of signs. Hence there are sixteen signatures in all, and all of them are proxy stronglyblind signature schemes. Furthermore, the two degenerated situations of multi-linear transform are discussed. Their corresponding proxy blind signature schemes are shown, too. But some schemes come from one of these degenerate situations are proxy weakly-blind signature scheme.The security for proposed scheme is analyzed in details. The results indicate that these signature schemes have many good properties such as unforgeability, distinguish-ability of proxy signature,non-repudiation and extensive value of application etc.

A NEW EFFICIENT ID-BASED PROXY BLIND SIGNATURE SCHEME

In a proxy blind signature scheme,the proxy signer is allowed to generate a blind signature on behalf of the original signer. The proxy blind signature scheme is useful in several applications such as e-voting,e-payment,etc. Recently,Zheng,et al. presented an IDentity(ID) -based proxy blind sig-nature. In this paper,a new efficient ID-based proxy blind signature scheme from bilinear pairings is proposed,which can satisfy the security properties of both the proxy signatures and the blind signature schemes. Analysis of the scheme efficiency shows that the new scheme is more efficient than Zheng,et al.'s scheme. The proposed scheme is more practical in the real world.

Protection of mobile location privacy by using blind signature

Location privacy means a user keeps his/her geographical location secret. If location information falls into the wrong hands, an adversary can physically locate a person. To address this privacy issue, Qi et al.(2004a; 2004b) proposed a special and feasible architecture, using blind signature to generate an authorized anonymous ID replacing the real ID of a legitimate mobile user. The original purpose of his architecture was to eliminate the relationship of authorized anonymous ID and real ID. We present an algorithm to break out Qi’s registration and re-confusion protocol, and then propose a new mechanism based on bilinear pairings to protect location privacy. Moreover we show that the administrator or third parity cannot obtain information on the legitimate user’s authorized anonymous ID and real ID in our proposed protocols.