Quantum digital signature in a network

Maksim Iavich, Giorgi Iashvili, Răzvan Bocu +1 more

Hua‐Lei Yin, Wei-Long Wang, Yan-Lin Tang +16 more

Quantum digital signatures (QDSs) provide a means for signing electronic communications with information-theoretic security. However, all previous demonstrations of quantum digital signatures assume trusted measurement devices. This renders them vulnerable against detector side-channel attacks, just like quantum key distribution. Here we exploit a measurement-device-independent (MDI) quantum network, over a metropolitan area, to perform a field test of a three-party MDI QDS scheme that is secure against any detector side-channel attack. In so doing, we are able to successfully sign a binary message with a security level of about ${10}^{\ensuremath{-}7}$. Remarkably, our work demonstrates the feasibility of MDI QDSs for practical applications.

Pardeep Singh Tiwana, Soumen Sardar, Gagandeep Kaur +1 more

Hua‐Lei Yin, Yao Fu, Chen-Long Li +6 more

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 integrity, authenticity and non-repudiation of data with information-theoretical security are highly urgent and intractable open problems in cryptography. Here, we propose a high-efficiency quantum digital signature (QDS) protocol using asymmetric quantum keys acquired via secret sharing, one-time universal2 hashing and a one-time pad. We just need to use a 384-bit key to sign documents of lengths up to 264 with a security bound of 10−19. If a one-megabit document is signed, the signature efficiency is improved by more than 108 times compared with previous QDS 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.

Eleni Diamanti, Romain Alléaume, Anthony Leverrier +8 more

Joseph C. Chapman, Muneer Alshowkan, Bing Qi +1 more

The quantum digital signature protocol offers a replacement for aspects of public-key digital signatures. Here, we demonstrate and characterize hardware to implement entanglement-based quantum digital signatures over our campus network, validating use in deployed fiber.