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arXiv · 0906.1671

Two-Party Quantum Protocols Do Not Compose Securely Against Honest-But-Curious Adversaries

Louis Salvail·Miroslava Sotakova
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Abstract

In this paper, we build upon the model of two-party quantum computation introduced by Salvail et al. [SSS09] and show that in this model, only trivial correct two-party quantum protocols are weakly self-composable. We do so by defining a protocol Π, calling any non-trivial sub-protocol πN times and showing that there is a quantum honest-but-curious strategy that cannot be modeled by acting locally in every single copy of π. In order to achieve this, we assign a real value called "payoff" to any strategy for Πand show that that there is a gap between the highest payoff achievable by coherent and local strategies.

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Louis Salvail, Miroslava Sotakova. 2009-06-15. Two-Party Quantum Protocols Do Not Compose Securely Against Honest-But-Curious Adversaries. https://arxiv.org/abs/0906.1671

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