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Simple Proof of Security of the BB84 Quantum Key Distribution Protocol

Peter W. Shor·John Preskill
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Abstract

We prove the security of the 1984 protocol of Bennett and Brassard (BB84) for quantum key distribution. We first give a key distribution protocol based on entanglement purification, which can be proven secure using methods from Lo and Chau's proof of security for a similar protocol. We then show that the security of this protocol implies the security of BB84. The entanglement-purification based protocol uses Calderbank-Shor-Steane (CSS) codes, and properties of these codes are used to remove the use of quantum computation from the Lo-Chau protocol.

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Peter W. Shor, John Preskill. 2000-05-12. Simple Proof of Security of the BB84 Quantum Key Distribution Protocol. https://doi.org/10.1103/physrevlett.85.441

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