Improving Classical Authentication over a Quantum Channel

Entropy

Francisco M. Assis¹  Aleksandar Stojanovic²  Paulo Mateus² 

[1] Department of Electrical Engineering, Universidade Federal de Campina Grande, 58.429-970 Campina Grande, Paraíba, Brazil; E-Mail:;Department of Mathematics, IST, Technical University of Lisbon, 1049-001 Lisboa, Portugal; E-Mail:

关键词: quantum communication;    quantum authentication;    quantum key maintenance;    QKD recovery;    entropy bound;   

DOI  :  10.3390/e14122531

来源: mdpi

【 摘 要 】

We propose a quantum protocol to authenticate classical messages that can be used to replace Wegman–Carter’s classical authentication scheme in quantum key distribution (QKD) protocols. We show that the proposed scheme achieves greater conditional entropy of the seed for the intruder given her (quantum) observation than the classical case. The proposed scheme is suitable for situations where the shared symmetric key used in authentication becomes dangerously short (due to noise or eavesdropping), and there is a threat that it might be completely consumed without being replaced. Our protocol is an improvement over a classical scheme by Brassard and takes advantage of quantum channel properties. It is motivated by information-theoretical results. We stress that the proposed authentication protocol can also be used as an independent authentication protocol that is not a part of a QKD. However by adopting it, QKD becomes a fully quantum protocol. We prove that quantum resources can improve both the secrecy of the key generated by the PRG and the secrecy of the tag obtained with a hidden hash function. We conclude that the proposed quantum encoding offers more security than the classical scheme and, by applying a classical result, we show that it can be used under noisy quantum channels.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.