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arXiv · 1807.04472

Finite-key effects in multi-partite quantum key distribution protocols

Federico Grasselli·Hermann Kampermann·Dagmar Bruß
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Abstract

We analyze the security of two multipartite quantum key distribution (QKD) protocols, specifically we introduce an $N$-partite version of the BB84 protocol and we discuss the $N$-partite six-state protocol proposed in arXiv:1612.05585v2. The security analysis proceeds from the generalization of known results in bipartite QKD to the multipartite scenario, and takes into account finite resources. In this context we derive a computable expression for the achievable key rate of both protocols by employing the best-known strategies: the uncertainty relation and the postselection technique. We compare the performances of the two protocols both for finite resources and infinitely many signals.

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Federico Grasselli, Hermann Kampermann, Dagmar Bruß. 2018-07-12. Finite-key effects in multi-partite quantum key distribution protocols. https://doi.org/10.1088/1367-2630/aaec34

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