Information-theoretically secure data origin authentication with quantum and classical resources

TL;DR

This paper investigates whether quantum resources can enhance information-theoretically secure message authentication, concluding that passive schemes cannot outperform classical methods, but interactive entanglement-assisted schemes can authenticate messages efficiently.

Contribution

The paper introduces an interactive entanglement-assisted quantum scheme that achieves message authentication with a key as long as the message, surpassing classical passive methods.

Findings

Passive quantum schemes do not outperform classical schemes.

Interactive entanglement-assisted schemes can authenticate messages efficiently.

Quantum resources enable new authentication protocols with shorter keys.

Abstract

In conventional cryptography, information-theoretically secure message authentication can be achieved by means of universal hash functions, and requires that the two legitimate users share a random secret key, which is twice as long as the message. We address the question as of whether quantum resources can offer any advantage over classical unconditionally secure message authentication codes. It is shown that passive prepare-and-measure quantum message-authentication schemes cannot do better than their classical counterparts. Subsequently we present an interactive entanglement-assisted scheme, which ideally allows for the authentication of classical messages with a classical key, which is as long as the message.