Revisiting the security of quantum dialogue and bidirectional quantum secure direct communication

TL;DR

This paper critically examines the security of certain quantum communication protocols, revealing information leakage issues that challenge their assumed confidentiality and calling for further research to address these vulnerabilities.

Contribution

It identifies and analyzes security flaws in existing quantum dialogue and QSDC protocols, highlighting the need for improved security measures.

Findings

Information leakage in protocols

Eavesdropper can extract secret info

Existing protocols have security vulnerabilities

Abstract

From the perspective of information theory and cryptography, we analyze the security of two quantum dialogue protocols and a bidirectional quantum secure direct communication (QSDC) protocol, and point out that the transmitted information would be partly leaked out in them. That is, any eavesdropper can elicit some information about the secrets from the public annunciations of the legal users. This phenomenon should have been strictly forbidden in a quantum secure communication. In fact, this problem exists in quite a few recent proposals and, therefore, it deserves more research attention in the following related study.