Unconditional security of coherent-state-based differential phase shift quantum key distribution protocol with block-wise phase randomization

Kiyoshi Tamaki; Masato Koashi; Go Kato

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arXiv · 1208.1995

Unconditional security of coherent-state-based differential phase shift quantum key distribution protocol with block-wise phase randomization

Kiyoshi Tamaki·Masato Koashi·Go Kato

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Abstract

We prove the unconditional security of coherent-state-based differential phase shift quantum key distribution protocol (DPSQKD) with block-wise phase randomization. Our proof is based on the conversion of DPSQKD to an equivalent entanglement-distillation protocol where the estimated phase error rate determines the amount of the privacy amplification. The generated final key has a contribution from events where the sender emits two or more photons, indicating the robustness of DPSQKD against photon-number-splitting attacks.

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Kiyoshi Tamaki, Masato Koashi, Go Kato. 2012-08-09. Unconditional security of coherent-state-based differential phase shift quantum key distribution protocol with block-wise phase randomization. https://arxiv.org/abs/1208.1995

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