Efficient quantum direct communication with authentication

TL;DR

This paper introduces two secure and efficient quantum direct communication protocols with authentication, resistant to attacks from both the authenticator and external eavesdroppers, and extends them to multiparty scenarios.

Contribution

The paper proposes novel quantum communication protocols using four Pauli operations that are secure against specific attack models and generalizes them to multiparty communication.

Findings

Protocols are secure against Trent's and Eve's attacks.

Protocols are efficient and extendable to multiparty communication.

Security is achieved using four Pauli operations.

Abstract

Two protocols of quantum direct communication with authentication [Phys. Rev. A 73, 042305(2006)] were recently indicated to be insecure against the authenticator Trent's attacks [Phys. Rev. A 75, 026301(2007)]. We present two efficient protocols by using four Pauli operations, which are secure against inner Trent's attacks as well as outer Eve's attacks. Finally, we generalize them to multiparty quantum direction communication.