Efficient Mediated Semi-Quantum Key Distribution Protocol Using Single Qubits

TL;DR

This paper introduces a more practical mediated semi-quantum key distribution protocol that minimizes quantum requirements for the third party, maintaining security while simplifying implementation.

Contribution

The proposed protocol reduces quantum demands on the untrusted third party, enabling easier practical deployment without sacrificing security or efficiency.

Findings

Protocol is secure against common attacks.

Reduces quantum requirements for the third party.

Maintains high qubit efficiency.

Abstract

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 $X$ basis. Meanwhile, the classical participants are limited to preparing and measuring qubits in the $Z$ 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.