# Robust Protocols for Securely Expanding Randomness and Distributing Keys Using Untrusted Quantum Devices

@article{Miller2016RobustPF, title={Robust Protocols for Securely Expanding Randomness and Distributing Keys Using Untrusted Quantum Devices}, author={Carl A. Miller and Yaoyun Shi}, journal={Journal of the ACM (JACM)}, year={2016}, volume={63}, pages={1 - 63} }

Randomness is a vital resource for modern-day information processing, especially for cryptography. A wide range of applications critically rely on abundant, high-quality random numbers generated securely. Here, we show how to expand a random seed at an exponential rate without trusting the underlying quantum devices. Our approach is secure against the most general adversaries, and has the following new features: cryptographic level of security, tolerating a constant level of imprecision in…

## 40 Citations

Robust protocols for securely expanding randomness and distributing keys using untrusted quantum devices

- Physics, MathematicsSTOC
- 2014

This work shows how to expand a random seed at an exponential rate without trusting the underlying quantum devices, and has the following new features: tolerating a constant level of implementation imprecision, requiring only a unit size quantum memory per device component for the honest implementation, and allowing a large natural class of constructions.

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- Computer Science, PhysicsSIAM J. Comput.
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A flexible protocol is provided and a security proof is given that provides quantitative bounds that are asymptotically tight, even in the presence of general quantum adversaries, which is likely that these protocols can be practically implemented in the near future.

Device-independent quantum key distribution with random key basis

- Physics, MedicineNature communications
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This work significantly narrows the gap between the theory and practice of DIQKD with a simple variant of the original protocol based on the celebrated Clauser-Horne-Shimony-Holt (CHSH) Bell inequality, and shows that the proposed protocol significantly improves over the original DIZKD protocol, enabling positive keys in the high noise regime for the first time.

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- Medicine, Computer ScienceNature
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Genuine, unpredictable quantum random-number generation that is provably secure against quantum and classical adversaries is demonstrated, certified by the loophole-free violation of a Bell inequality.

Certifiable Randomness from a Single Quantum Device

- Computer ScienceArXiv
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The randomness protocol can be used as the basis for an efficiently verifiable quantum supremacy proposal, thus answering an outstanding challenge in the field.

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- Physics, Computer ScienceQuantum
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A two-device protocol for DI random number generation (DIRNG) which produces approximatelynbits of randomness starting fromnpairs of arbitrarily weakly entangled qubits and it is shown that the numberm of singlet states need only scale sublinearly with the number of random bits produced.

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- Physics, Computer ScienceNature
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1,024 random bits that are uniformly distributed to within 10−12 and unpredictable assuming the impossibility of superluminal communication are generated and certified using a loophole-free Bell test and a protocol is described that is optimized for devices that are characterized by a low per-trial violation of Bell inequalities.

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- Physics, MedicineCommun. ACM
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This work rigorously proves the device-independent security of an entanglement-based protocol building on Ekert's original proposal for quantum key distribution and builds on techniques from the classical theory of pseudo-randomness to achieve a new quantitative understanding of the non-local nature of quantum correlations.

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- Physics, Computer ScienceQuantum Science and Technology
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A fully finite size analysis of device independent protocols using the CHSH inequality both for collective and coherent attacks and describes experimental improvements that can lead to a device-independent quantum key distribution implementation in the near future.

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The authors present a proof-of principle implementation of a device-independent random number generator protocol, whose effectiveness is certified by quantum instrumental correlations, which also ensures privacy with respect to any quantum adversarial attack.

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