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arXiv · 2504.20417

Protocol-level description and self-contained security proof of decoy-state BB84 QKD protocol

Akihiro Mizutani·Toshihiko Sasaki·Go Kato
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Abstract

In this paper, we present a flowchart-based description of the decoy-state BB84 quantum key distribution (QKD) protocol and provide a step-by-step, self-contained information-theoretic security proof for this protocol within the universal composable security framework. As a result, our proof yields a key rate consistent with previous findings. Importantly, unlike all the prior security proofs, our approach offers a fully rigorous and mathematical justification for achieving the key rate with the claimed correctness and secrecy parameters, thereby representing a significant step toward the formal certification of QKD systems.

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Akihiro Mizutani, Toshihiko Sasaki, Go Kato. 2025-05-26. Protocol-level description and self-contained security proof of decoy-state BB84 QKD protocol. https://arxiv.org/abs/2504.20417

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