Comment on “Quantum private comparison of equality protocol without a third party”

Abstract In this paper, by using swap test, a quantum private comparison (QPC) protocol of arbitrary single qubit states with a semi-honest third party is proposed. The semi-honest third party (TP) is required to help two participants perform the comparison. She can record intermediate results and do some calculations in the whole process of the protocol execution, but she cannot conspire with any participants. In the process of comparison, TP cannot get two participants' private information except the comparison results. According to the security analysis, the proposed protocol can resist both outsider attacks and participant attacks. Compared with the existing QPC protocols, the proposed one does not require any entanglement swapping technology, and it can compare two participants' qubits by performing swap test, which is easier to implement with current technology. Meanwhile, the proposed protocol can compare secret integers. It encodes secret integers into the amplitude of quantum state rather than transfer them as binary representations, and the encoded quantum state is compared by performing swap test. Additionally, the proposed QPC protocol is extended to the QPC of arbitrary single qubit states by using multi-qubit swap test.

Download Full-text

CRYPTANALYSIS AND IMPROVEMENTS FOR THE QUANTUM PRIVATE COMPARISON PROTOCOL USING EPR PAIRS

International Journal of Quantum Information ◽

10.1142/s0219749913500391 ◽

2013 ◽

Vol 11 (04) ◽

pp. 1350039 ◽

Cited By ~ 21

Author(s):

CONG WANG ◽

GANG XU ◽

YI-XIAN YANG

Keyword(s):

Third Party ◽

Quantum Private Comparison ◽

Secret Information ◽

Epr Pairs ◽

Private Comparison ◽

Depth Analysis ◽

Feasible Solutions

In this paper, we carry out an in-depth analysis of the quantum private comparison (QPC) protocol with the semi-honest third party (TP). The security of QPC protocol using the EPR pairs is re-examined. Unfortunately, we find that TP can use the fake EPR pairs to steal all the secret information. Furthermore, we give two simple and feasible solutions to improve the original QPC protocol. It is shown that the improved protocol is secure, which can resist various kinds of attacks from both the outside eavesdroppers and the inside participants, even the semi-honest TP.

Download Full-text

Multi-party quantum private comparison with an almost-dishonest third party

Quantum Information Processing ◽

10.1007/s11128-015-1104-z ◽

2015 ◽

Vol 14 (11) ◽

pp. 4225-4235 ◽

Cited By ~ 23

Author(s):

Sheng-Liang Huang ◽

Tzonelih Hwang ◽

Prosanta Gope

Keyword(s):

Third Party ◽

Quantum Private Comparison ◽

Private Comparison

Download Full-text

Quantum private comparison of equality protocol without a third party

Quantum Information Processing ◽

10.1007/s11128-013-0645-2 ◽

2013 ◽

Vol 13 (2) ◽

pp. 239-247 ◽

Cited By ~ 23

Author(s):

Jason Lin ◽

Chun-Wei Yang ◽

Tzonelih Hwang

Keyword(s):

Third Party ◽

Quantum Private Comparison ◽

Private Comparison

Download Full-text

Cryptanalysis of He’s quantum private comparison protocol and a new protocol

International Journal of Quantum Information ◽

10.1142/s0219749919500266 ◽

2019 ◽

Vol 17 (03) ◽

pp. 1950026 ◽

Cited By ~ 3

Author(s):

WanQing Wu ◽

QingYu Cai ◽

ShuoMei Wu ◽

HuanGuo Zhang

Keyword(s):

Third Party ◽

Quantum Private Comparison ◽

Private Comparison

Recently, He proposed a novel quantum private comparison protocol without a third party (G. P. He, Int. J. Quantum Inf. 15(2) (2016) 1750014). This paper points out that two security loopholes in He’s protocol are existent. And a new QPC protocol which can avoid these loopholes is proposed without the help of a third party in this paper.

Download Full-text

Orthogonal-state-based and semi-quantum protocols for quantum private comparison in noisy environment

International Journal of Quantum Information ◽

10.1142/s0219749918500478 ◽

2018 ◽

Vol 16 (05) ◽

pp. 1850047 ◽

Cited By ~ 14

Author(s):

Kishore Thapliyal ◽

Rishi Dutt Sharma ◽

Anirban Pathak

Keyword(s):

Quantum State ◽

Third Party ◽

Quantum Private Comparison ◽

Noisy Environment ◽

Private Comparison ◽

Orthogonal State ◽

Quantum Protocols ◽

Noise Models ◽

Computational Basis

Private comparison is a primitive for many cryptographic tasks, and recently several schemes for the quantum private comparison (QPC) have been proposed, where two users can compare the equality of their secrets with the help of a semi-honest third party (TP) without knowing each other’s secret and without disclosing the same to the TP. In the existing schemes, secrecy is obtained by using conjugate coding, and considering all participants as quantum users who can perform measurement(s) and/or create states in basis other than computational basis. In contrast, here we propose two new protocols for QPC, first of which does not use conjugate coding (uses orthogonal states only) and the second one allows the users other than TP to be classical whose activities are restricted to either reflecting a quantum state or measuring it in computational basis. Further, the performance of the protocols is evaluated under various noise models.

Download Full-text

Two-party quantum private comparison protocol with maximally entangled seven-qubit state

Modern Physics Letters A ◽

10.1142/s0217732319502298 ◽

2019 ◽

Vol 34 (28) ◽

pp. 1950229 ◽

Cited By ~ 3

Author(s):

ZhaoXu Ji ◽

HuanGuo Zhang ◽

PeiRu Fan

Keyword(s):

Quantum Key Distribution ◽

Data Privacy ◽

Entanglement Swapping ◽

Qubit State ◽

Third Party ◽

Quantum Private Comparison ◽

Secret Data ◽

Particle Measurements ◽

Private Comparison ◽

Cooperative Computing

Quantum private comparison (QPC), whose security is based on some laws of quantum mechanics (e.g. quantum noncloning theorem and Heisenbergs uncertainty principle), allows [Formula: see text] parties who do not trust each other to judge whether their secret data are the same while maintaining data privacy. In this paper, we investigate the utility of the maximally entangled seven-qubit state for QPC, and we propose a new protocol which enables two parties to compare their secret data with each other for equality without disclosing their secret data. In our protocol, single particle measurements and Bell-basis measurements are employed, both of which can be implemented with current technologies. In addition to quantum measurements, our protocol does not use other quantum technologies such as entanglement swapping and unitary operations. A semi-honest third-party who assists two parties in implementing the protocol is assumed in our protocol. Furthermore, we use the entanglement correlations of the maximally entangled seven-qubit state and collaborative computing between parties for privacy protection, and we use quantum key distribution (QKD) to ensure the security of the cooperative computing when two parties are in different locations. What is more, we show that the security towards both outsider and insider attacks can be guaranteed.

Download Full-text