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arXiv · 2107.14089

Experimental quantum secure network with digital signatures and encryption

Hua-Lei Yin·Yao Fu·Chen-Long Li·Chen-Xun Weng·Bing-Hong Li·Jie Gu·Yu-Shuo Lu·Shan Huang·Zeng-Bing Chen
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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.

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Hua-Lei Yin, Yao Fu, Chen-Long Li, Chen-Xun Weng, Bing-Hong Li, Jie Gu, Yu-Shuo Lu, Shan Huang, Zeng-Bing Chen. 2021-07-29. Experimental quantum secure network with digital signatures and encryption. https://doi.org/10.1093/nsr%2Fnwac228

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