Experimental quantum secure network with digital signatures and encryption

TL;DR

This paper introduces a highly efficient quantum digital signature protocol that enhances security and performance, and demonstrates an all-in-one quantum secure network integrating multiple cryptographic functions.

Contribution

It presents a novel quantum digital signature protocol with unprecedented efficiency and builds the first comprehensive quantum secure network combining multiple security features.

Findings

Signatures of up to 2^64 length with a 384-bit key and security bound of 10^-19.

Signature efficiency improved by over 10^8 times compared to previous protocols.

Experimental demonstration of an integrated quantum secure network.

Abstract

Cryptography promises four information security objectives, namely, confidentiality, integrity, authenticity, and non-repudiation, to support trillions of transactions annually in the digital economy. Efficient digital signatures, ensuring the integrity, authenticity, and non-repudiation of data with information-theoretical security are highly urgent and intractable open problems in cryptography. Here, we propose a protocol of high-efficiency quantum digital signatures using secret sharing, one-time universal$_2$ hashing, and the one-time pad. We just need to use a 384-bit key to sign documents of up to $2^{64}$ lengths with a security bound of $10^{-19}$. If one-megabit document is signed, the signature efficiency is improved by more than $10^8$ times compared with previous quantum digital signature protocols. Furthermore, we build the first all-in-one quantum secure network integrating information-theoretically secure communication, digital signatures, secret sharing, and conference key agreement and experimentally demonstrate this signature efficiency advantage. Our work completes the cryptography toolbox of the four information security objectives.