Abstract The authors present a novel token exchange scheme with an example of an electronic cash (eCash) transaction scheme that ensures quantum security, addressing the vulnerabilities of existing models in the face of quantum computing threats. The authors’ comprehensive analysis of various quantum blind signature mechanisms revealed significant shortcomings in their applicability to eCash transactions and their resilience against quantum adversaries. In response, the authors drew inspiration from D. Chaum's original classical eCash scheme and innovated a quantum‐secure transaction framework. The authors detail the developed protocol and rigorously evaluate its security aspects. The protocol's adherence to critical security requirements such as blindness, non‐forgeability, non‐deniability, and prevention of double spending is analysed. Moreover, the scheme against Intercept and Resend, Denial of Service, Man‐in‐the‐Middle, and Entangle‐and‐Measure attacks is rigorously tested. The authors’ findings indicate a robust eCash transaction model capable of withstanding the challenges posed by quantum computing advancements.
Abstract The authors present a novel token exchange scheme with an example of an electronic cash (eCash) transaction scheme that ensures quantum security, addressing the vulnerabilities of existing models in the face of quantum computing threats. The authors’ comprehensive analysis of various quantum blind signature mechanisms revealed significant shortcomings in their applicability to eCash transactions and their resilience against quantum adversaries. In response, the authors drew inspiration from D. Chaum's original classical eCash scheme and innovated a quantum‐secure transaction framework. The authors detail the developed protocol and rigorously evaluate its security aspects. The protocol's adherence to critical security requirements such as blindness, non‐forgeability, non‐deniability, and prevention of double spending is analysed. Moreover, the scheme against Intercept and Resend, Denial of Service, Man‐in‐the‐Middle, and Entangle‐and‐Measure attacks is rigorously tested. The authors’ findings indicate a robust eCash transaction model capable of withstanding the challenges posed by quantum computing advancements.
ABSTRACT Recently, a quantum blind signature scheme based on the ‐state for quantum supply chain finance has been proposed, which utilizes blindness to protect the privacy of participating firms. However, our analysis found that this scheme cannot resist the intercept‐measurement‐resend attack and the entanglement‐measurement attack, and the blind operation is ineffective against the insider attacker. Importantly, the blind signer can achieve existential forgery through a valid signature. Then, an improved scheme was proposed that reduces quantum bit consumption, eliminates the need for quantum state swap tests, and extends the message space for signatures to the more universal classical bit space. We have constructed a security model that formally defines the security properties and adversary capabilities of the quantum blind signature. Through this model, the blindness and unforgeability of the improved scheme are reduced to the principles of quantum mechanics in four games. The vulnerabilities of the original scheme and the feasibility of the improved scheme in quantum computing have been verified through the Qiskit simulator.
Hybrid cryptographic protocol was proposed by integrating quantum-safe algorithms (Kyber and Dilithium) together with a classical ECDSA-based signature scheme to verify secure proof on blockchain. Since quantum computers pose some loopholes in existing cryptography algorithms, the proposed mechanism addresses those vulnerabilities by maintaining compatibility with the existing infrastructure. The protocol integrates post-quantum key exchange to derive shared secrets securely. The shared secrets are used to enable hybrid encryption for efficient data protection. Additionally, the implementation uses a dual-signature approach, using quantum safe and classical signatures. These signatures are combined to ensure robust and tamper-resistant proof verification. The deployed solution validates its feasibility and efficiency for smart contract-based verification. The protocol maintains backward compatibility with existing systems while providing strong resistance to quantum attacks. Benchmark results demonstrate the system’s scalability and robustness under high transaction loads, with efficient gas usage for on-chain proof validation. This approach paves the way for post-quantum secure applications, including verifiable proofs, secure key exchanges, and decentralized systems resilient to quantum adversaries.
On-line merchants must have security protocol and procedures in place to carry out transactions more securely, Due to the popularity of e-commerce payment systems and the widespread use of the internet-based shopping and banking. In this paper we introduce an original blind signature based on quantum cryptographic principles providing unconditional security for off-line transactions. The proposed scheme guarantees the security of payment in real applications by the laws of quantum mechanics. We describe our proposed scheme in detail through a real example and discuss about its unconditional security.
Abstract With the development of information society, people are increasingly concerned about the security problems caused by information leakage, and digital signatures play an irreplaceable and important role in the protection of information security, which replace traditional manual signatures and seals in the network environment and have important roles such as anti-forgery, anti-tampering, anti-replay, identifiable identity and confidentiality [1]. However, with the in-depth study of quantum mechanics, it has been found that the confidentiality mechanism of classical digital signatures is under serious threat. Since quantum computing is a parallel operation with exponentially increasing operational capability, a series of complex mathematically difficult problems can be rapidly overcome. Based on the above, this paper proposes a multiple agent blind signature scheme, which adopts the key technologies such as the Unitary transformation and Hadamard gate operation, and adds multiple agent signature to quantum signature to improve the efficiency of the protocol, and adds blind signature to improve the security of the protocol. At the same time, the scheme uses quantum key distribution to ensure its unconditional security, which is applicable in systems such as electronic voting and electronic payment, and has certain anti-attack capability [2].
In order to solve the security of electronic transactions on limited goods, some quantum blind double signature (QBDS) protocols were proposed. In existing QBDS protocols, all participants must have specific quantum computing capabilities. Realistically, high cost of quantum devices may hinder people from using the QBDS protocol. Therefore, we propose a semi-quantum arbitrator blind double signature (SQABDS) scheme. In this scheme, the sender (signer) and the receiver both are classical participants, which can relatively reduce the dependence on quantum hardware. The introduction of blind signers can protect the privacy of electronic transactions, the introduction of semi-trusted arbitrator can relax the strong assumption about the trustworthiness of the arbitrator, for the arbitrator cannot forge the signature. In addition, the SQABDS scheme can be used to sign classical messages directly without performing any quantum swapping tests or quantum gate operations. Finally, the analysis shows that our scheme is securer and its quantum cost is relatively lower.
With the in-depth development of the digital economy and the escalating demands for transaction security and quantum attack resistance in electronic payment scenarios, quantum signature is gradually emerging as a core research direction in the construction of electronic payment security systems. Addressing the requirements for anonymity and security in electronic payment scenarios, this paper proposes an electronic payment scheme based on controlled quantum teleportation. During the implementation of the scheme, the quantum entanglement characteristics of the four-particle entangled state, the core logic of controlled quantum teleportation, the privacy protection features of proxy blind signature technology, and the technical advantages of superdense coding are integrated to provide security guarantees for the payment process. Meanwhile, the proposed scheme builds a payment system relying on quantum key distribution protocols, forming a payment system with information-theoretic security attributes. This effectively overcomes the limitation that traditional UnionPay payment systems rely on computational complexity at the security level. In addition, the scheme satisfies nonrepudiation and unforgeability and possesses the capability to resist interception-resending attacks.