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Journal of Chinese Computer Systems

Quantum Private Comparison Without Entanglement

YU Chao-hu

Published Jan 1, 2014• 1 citation
OpenAlex

Abstract

In this paper,a quantum private comparison protocol based on d dimensional single-particle states is proposed. In the protocol,a semi-honest third party transfers a sequence of n particles to one participant w ho encodes n secret keys by performing n local unitary operations. Then these particles are sent to the other participant w ho also by the same w ay encodes n secret keys and returns these particles back to the semi-honest party. Finally after the participants broadcast the results of encrypting their secrets w ith secret keys,the semi-honest third party can help the tw o participants compare the size relationships of their n pair corresponding secrets w ithout disclosing them to any other people. In addition,the security of the protocol is also discussed in detail. It is show n that the protocol is secure in theory. Moreover,since only single-particle states are used,as compared w ith other quantum private comparison protocols,the presented protocol is more feasible under the current technical conditions.

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In this paper,a quantum private comparison protocol based on d dimensional single-particle states is proposed. In the protocol,a semi-honest third party transfers a sequence of n particles to one participant w ho encodes n secret keys by performing n local unitary operations. Then these particles are sent to the other participant w ho also by the same w ay encodes n secret keys and returns these particles back to the semi-honest party. Finally after the participants broadcast the results of encrypting their secrets w ith secret keys,the semi-honest third party can help the tw o participants compare the size relationships of their n pair corresponding secrets w ithout disclosing them to any other people. In addition,the security of the protocol is also discussed in detail. It is show n that the protocol is secure in theory. Moreover,since only single-particle states are used,as compared w ith other quantum private comparison protocols,the presented protocol is more feasible under the current technical conditions.
Abstract In this paper, we propose two multi-party quantum private comparison protocols based on the properties of the d-dimensional GHZ state. Protocol 1 is designed to compare the equality of multiple participants’ secrets with the help of a semi-honest third party TP. The semi-honest TP will follow the protocol honestly, but he may attempt to learn additional information from the protocol execution. In this protocol, multiple participants encode their secret information into the corresponding particles in turn through unitary operations, thereby achieving the comparison of the equality of their multiple secrets in a single execution. This protocol has a wide range of applications. For example, by combining the basic model framework of this protocol with the Chinese Remainder Theorem, we propose Protocol 2. In this protocol, multiple participants compare the size relationships of their multiple secrets with the help of a semi-honest third party TP. Therefore, based on the same basic model framework, the two protocols proposed in this paper can be applied respectively to the comparison of the equality and the size relationships of multiple participants’ secrets. Importantly, the two protocols do not require pre-shared keys. Security analysis shows that the proposed protocols can resist various attacks, including entangle-measure attack, intercept-resend attack, third party attacks, and participant attacks.
In this paper, we introduce a quantum private comparison (QPC) protocol designed for two players to securely and privately assess the equality of their private information. The protocol utilizes four-particle cluster states prepared by a semi-honest third party (TP), who strictly adheres to the protocol without deviation or collusion with any participant. The TP facilitates the private comparison by enabling users to encode their information through bit-flip or phase-shift operators applied to the received quantum sequences. Once the information is encoded, the sequences are returned to the TP, who can derive the comparison results without accessing any details of the private information. This design ensures correctness, privacy, and fairness throughout the process. The QPC protocol is robust against both external threats and participant attacks due to the incorporation of the decoy-state method and quantum key distribution techniques. Additionally, the protocol employs unitary operations and Bell-basis measurements, enhancing its technical feasibility for practical implementation. Notably, the proposed protocol achieves a qubit efficiency of up to 50%. This efficiency, combined with its strong security features, establishes the QPC protocol as a promising solution for private information comparisons within the realm of quantum cryptography.
Abstract Semi-quantum private comparison is a method for private comparison with fewer quantum resources, enabling classical participants to collaborate with a semi-honest third party possessing complete quantum capabilities. A one-way quantum private comparison protocol is devised only by unitary operations. The protocol facilitates one-way transmission between third party (TP) and classical participants in quantum communication, where the classical participants only need to perform unitary operations and measurement operations on the transmitted qubits. In addition, classical participants do not require pre-shared keys. It is shown that the qubit efficiency of this protocol is 12.5%. Finally, security analysis and the simulation results on the IBM Quantum Experience demonstrate the security and the feasibility of this protocol.
Abstract Based on Bell states, a new semi-quantum private comparison protocol is proposed that enables two classical users to securely compare the equality of their private information with the aid of a semi-honest third party. Different from the existing semi-quantum private comparison protocols, the two classical participants in the presented protocol do not need to measure and prepare any quantum state, which not only reduces the consumption of quantum devices, but also greatly improves the feasibility of the protocol. Performing different unitary operations on the received particles, classical users can securely compare their secret information. Besides, the devised protocol has higher qubit efficiency than the other similar counterparts, since participants can compare a two-bit privacy each time with one qubit. Meanwhile, after completing the comparison process, all Bell states could be reused since they still retain the corresponding entanglement property, which greatly facilitates the recycle of quantum resources. Security analyses indicate that the designed scheme is secure against external attack and internal attack. Moreover, the operations involved in our scheme are simulated on the IBM Quantum Experience to demonstrate the effectiveness and security of our scheme.
Abstract Based on d -dimensional multiparticle maximal entangled states, a novel multi-party private comparison protocol under semi-quantum condition is proposed. With the help of a semi-honest quantum third party, N classical participants can determine the size relationship of their privacies while keeping them private in the devised protocol. Compared with some similar protocols, the presented protocol performs better in terms of security and qubit efficiency. In addition, the effectiveness and the correctness of our protocol are verified with some examples and proofs. By the decoy particles and the pre-shared keys, the presented protocol can defend against the internal and the external attacks.