Comment on "Quantum Key Distribution with Classical Bob"

TL;DR

This paper introduces a frequency-shift attack on a quantum key distribution protocol with classical Bob, highlighting potential vulnerabilities in two-way quantum key distribution systems.

Contribution

It presents a practical frequency-shift attack that challenges the security assumptions of certain quantum key distribution protocols.

Findings

Identifies a new vulnerability in two-way QKD protocols

Demonstrates effectiveness of frequency-shift attack

Suggests need for improved security measures

Abstract

In this comment, we present a frequency-shift attack on "quantum key distribution with classical Bob". This practical attack should also be considered in other two-way quantum key distribution protocols.