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arXiv · 0903.3118

Quantum-Secure Coin-Flipping and Applications

Ivan Damgaard·Carolin Lunemann
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Abstract

In this paper, we prove classical coin-flipping secure in the presence of quantum adversaries. The proof uses a recent result of Watrous [Wat09] that allows quantum rewinding for protocols of a certain form. We then discuss two applications. First, the combination of coin-flipping with any non-interactive zero-knowledge protocol leads to an easy transformation from non-interactive zero-knowledge to interactive quantum zero-knowledge. Second, we discuss how our protocol can be applied to a recently proposed method for improving the security of quantum protocols [DFL+09], resulting in an implementation without set-up assumptions. Finally, we sketch how to achieve efficient simulation for an extended construction in the common-reference-string model.

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Ivan Damgaard, Carolin Lunemann. 2009-10-19. Quantum-Secure Coin-Flipping and Applications. https://arxiv.org/abs/0903.3118

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