A simple proof of security of the BB84 protocol is presented in this paper. The proof is achieved in an information-theoretic way without referring to the formalism of quantum error-correction codes. Two examples are presented and discussed, showing that some previous results are special cases of the framework in this paper. It is suggested that the proof here sheds new light on security analysis of quantum key distribution, and that its technique may also improve the studies of other quantum information tasks.

中文翻译：

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BB84量子密钥分发协议的安全性简单分析

本文提出了BB84协议安全性的简单证明。该证明是以信息论的方式实现的，而没有涉及量子纠错码的形式化。给出并讨论了两个示例，表明先前的一些结果是本文框架的特殊情况。提出的证明在此为量子密钥分配的安全性分析提供了新的思路，并且其技术还可以改善对其他量子信息任务的研究。