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arXiv:1909.02788 · Scientific Reports

Lightweight mediated semi-quantum key distribution protocol with a dishonest third party based on Bell states

Chia‐Wei Tsai, Chun‐Wei Yang

Published Dec 1, 2021• 35 citations
arXivHTMLPDF

Abstract

The mediated semi-quantum key distribution (MSQKD) protocol is an important research issue that lets two classical participants share secret keys securely between each other with the help of a third party (TP). However, in the existing MSQKD protocols, there are two improvable issues, namely (1) the classical participants must be equipped with expensive detectors to avoid Trojan horse attacks and (2) the trustworthiness level of TP must be honest. To the best of our knowledge, none of the existing MSQKD protocols can resolve both these issues. Therefore, this study takes Bell states as the quantum resource to propose a MSQKD protocol, in which the classical participants do not need a Trojan horse detector and the TP is dishonest. Furthermore, the proposed protocol is shown to be secure against well-known attacks and the classical participants only need two quantum capabilities. Therefore, in comparison to the existing MSQKD protocols, the proposed protocol is better practical.

DOI
10.1038/s41598-021-02614-3

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The mediated semi-quantum key distribution (MSQKD) protocol is an important research issue that lets two classical participants share secret keys securely between each other with the help of a third party (TP). However, in the existing MSQKD protocols, there are two improvable issues, namely (1) the classical participants must be equipped with expensive detectors to avoid Trojan horse attacks and (2) the trustworthiness level of TP must be honest. To the best of our knowledge, none of the existing MSQKD protocols can resolve both these issues. Therefore, this study takes Bell states as the quantum resource to propose a MSQKD protocol, in which the classical participants do not need a Trojan horse detector and the TP is dishonest. Furthermore, the proposed protocol is shown to be secure against well-known attacks and the classical participants only need two quantum capabilities. Therefore, in comparison to the existing MSQKD protocols, the proposed protocol is better practical.
Classical users can share a secret key with a quantum user by using a semi-quantum key distribution (SQKD) protocol. Allowing two classical users to share a secret key is the objective of the mediated semi-quantum key distribution (MSQKD) protocol. However, the existing MSQKD protocols need a quantum user to assist two classical users in distributing the secret keys, and these protocols require that the classical users be equipped with a Trojan horse photon detector. This reduces the practicability of the MSQKD protocols. Therefore, in this study we propose a lightweight MSQKD, in which the two participants and third party are classical users. Due to the usage of the one-way transmission strategy, the proposed lightweight MSQKD protocol is free from quantum Trojan horse attack. The proposed MSQKD is more practical than the existing MSQKD protocols.
Due to the exiting semi-quantum secret sharing protocol have two challenges including (1) the dealer must be the quantum user, and (2) the classical users must equip with the Trojan Horse detectors, this study wants to propose a novel mediate semi-quantum secret sharing (MSQSS) protocol to let a classical dealer can share his/her secrets to the classical agents with the help of a dishonest third-party (TP). The proposed MSQSS protocol adopts the one-way quantum communication and thus it is free from the Trojan Horse attacks. Furthermore, the security analysis is given for proving that the proposed protocol can be against the collective attack. Comparing to the exiting SQSS protocols, the proposed MSQSS protocol is more lightweight and more practical.
In this paper, we propose a new efficient mediated semi-quantum key distribution (MSQKD) protocol, facilitating the establishment of a shared secret key between two classical participants with the assistance of an untrusted third party (TP). Unlike existing MSQKD protocols, our approach significantly reduces the quantum requirements for TP, who only needs to prepare and measure qubits in the XXX basis. Meanwhile, the classical participants are limited to preparing and measuring qubits in the ZZZ basis, along with performing Hadamard operations. This reduction in quantum overhead enhances the practicality of our MSQKD protocol without compromising qubit efficiency. Additionally, we demonstrate the security of our protocol against various well-known attacks.
Abstract In this paper, we propose an efficient lightweight mediated semi-quantum key distribution (LM-SQKD) protocol, which enables two lightweight participants to securely establish a shared key with the help of an untrusted third party (TP). Compared with existing M-SQKD protocols, our protocol significantly reduces the overall quantum burden and improves the qubit efficiency, where TP only needs to prepare and measure qubits in the X basis and two lightweight participants are just required to execute three unitary operations and reflect qubits. Furthermore, the detailed security analysis verifies that the proposed protocol can against three well-known attacks.
This study proposes the first multiparty mediated semi-quantum secret sharing (MSQSS) protocol to overcome two existing challenges in current semi-quantum secret sharing protocols: (1) dealer must be the quantum user, and (2) classical users must be equipped with Trojan horse detectors. In the proposed MSQSS protocol, a classical dealer can share secrets with multiple classical agents via the help of a dishonest quantum third party. Security analysis is performed to prove that the proposed protocol cannot suffer from a collective attack, a collusion attack, or a Trojan horse attack. Furthermore, the proposed MSQSS protocol is more lightweight than existing SQSS protocols because the classical user is equipped with only two quantum capabilities.