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arXiv · 1503.01498

Finite key size analysis of two-way quantum cryptography

Jesni Shamsul Shaari·Stefano Mancini
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Abstract

Quantum cryptographic protocols solve the longstanding problem of distributing a shared secret string to two distant users by typically making use of one-way quantum channel. However, alternative protocols exploiting two-way quantum channel have been proposed for the same goal and with potential advantages. Here we overview a security proof for two-way quantum key distribution protocols, against the most general eavesdropping attack, that utilize an entropic uncertainty relation. Then, by resorting to the `smooth' version of involved entropies, we extend such a proof to the case of finite key size. The results will be compared to those available for one-way protocols showing some advantages.

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Jesni Shamsul Shaari, Stefano Mancini. 2015-03-04. Finite key size analysis of two-way quantum cryptography. https://doi.org/10.3390/e17052723

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