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Sequential attacks against differential-phase-shift quantum key distribution with weak coherent states

Marcos Curty·Lucy Liuxuan Zhang·Hoi-Kwong Lo·Norbert Lütkenhaus
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Abstract

We investigate limitations imposed by sequential attacks on the performance of differential-phase-shift quantum key distribution protocols that use pulsed coherent light. In particular, we analyze two sequential attacks based on unambiguous state discrimination and minimum error discrimination, respectively, of the signal states emitted by the source. Sequential attacks represent a special type of intercept-resend attacks and, therefore, they do not allow the distribution of a secret key.

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Marcos Curty, Lucy Liuxuan Zhang, Hoi-Kwong Lo, Norbert Lütkenhaus. 2006-09-12. Sequential attacks against differential-phase-shift quantum key distribution with weak coherent states. https://arxiv.org/abs/quant-ph/0609094

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