Quantum secure direct communication: Intersection of communication and cryptography

Yao–Hsin Chou, Kuo-Chun Tseng, Shu–Yu Kuo

Quantum-secure communication and computation have garnered increasing attention due to their powerful search capabilities for certain complex problems and their ability to provide unconditional security. This indicates that classical cryptography, such as asymmetric ciphers based on complex mathematics, faces a significant threat from quantum algorithms. However, quantum cryptography can detect any attempt to eavesdrop on a channel. As a result, the investigation and implementation of quantum computers and quantum-secure communication networks have become essential objectives for numerous research teams. This paper provides an overview of quantum cryptography, including its development, and focuses on the theoretical aspect of quantum secure direct communication (QSDC). This helps readers understand the theoretical operating principles and gain a better understanding of the entire quantum characteristic and protocol operation in the QSDC field. QSDC enables secure communication without previously shared private keys, making it a crucial topic in quantum cryptography research. This paper provides an overview of several well-known versions of QSDC in theory, discussing their applications, challenges and potential future directions.

A. Porzio

Gui‐Lu Long

Gui‐Lu Long

Quantum secure direct communication is one of the major branches of quantum cryptography. In quantum secure direct communication, secret information can be transmitted directly through a quantum channel without the use of a private key. Quantum secure direct communication(QSDC) offers higher security and instantaneousness in communication. Because it does not use private key, key management is dispensed with. Unlike quantum key distribution where key is transferred from quantum terminal to the classical terminal at the user's site, the coding operations are solely in the quantum terminal, it further provides security in the user's site. QSDC is also a powerful basic cryptographic primitive to build other quantum communication protocols, such as quantum bidding, quantum signature and quantum dialogue and so on. Here, we briefly introduce the basic ideas of QSDC, describe the major protocols, report current status, and give a perspective.

Xin LÜ

The notion of quantum secure direct communication (QSDC) has been introduced recently in quantum cryptography as a replacement for quantum key distribution, in which two communication entities exchange secure classical messages without establishing any shared keys previously. In this paper, a quantum secure direct communication scheme using quantum Calderbank-Shor-Steane (CSS) error correction codes is proposed. In the scheme, a secure message is first transformed into a binary error vector and then encrypted (decrypted) via quantum coding (decoding) procedures. An adversary Eve, who has controlled the communication channel, can't recover the secrete messages because she doesn't know the deciphering keys. Security of this scheme is based on the assumption