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A Quantum solution to the Byzantine agreement problem

Matthias Fitzi·Nicolas Gisin·Ueli Maurer
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Abstract

We present a solution to an old and timely problem in distributed computing. Like Quantum Key Distribution (QKD), quantum channels make it possible to achieve taks classically impossible. However, unlike QKD, here the goal is not secrecy but agreement, and the adversary is not outside but inside the game, and the resources require qutrits.

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Matthias Fitzi, Nicolas Gisin, Ueli Maurer. 2001-07-25. A Quantum solution to the Byzantine agreement problem. https://doi.org/10.1103/physrevlett.87.217901

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