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arXiv · 1308.2212

Security limitation on a class of device-independent quantum key distribution

Guang Ping He
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Abstract

Recently there were many proposals on device-independent (DI) quantum key distribution protocol whose security is based on the violation of the Clauser-Horne-Shimony-Holt inequality. However, as a statistical law, a certain extent of fluctuation has to be allowed. We show that the eavesdropper can make use of this property to obtain a remarkable part of the secret key by replacing some of the DI nonlocal boxes with local ones. On the contrary, the same cheating strategy does not apply to the device-dependent (DD) version of the protocol. Thus such kind of DI protocol is less secure than its DD counterpart.

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Guang Ping He. 2013-08-09. Security limitation on a class of device-independent quantum key distribution. https://arxiv.org/abs/1308.2212

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