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arXiv · 1805.02372

High-speed Implementation of Length-compatible Privacy Amplification in Continuous-variable Quantum Key Distribution

Xiangyu Wang·Yi-Chen Zhang·Song Yu·Hong Guo
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Abstract

Privacy amplification is an indispensable step in postprocessing of continuous-variable quantum key distribution (CV-QKD), which is used to distill unconditional secure keys from identical corrected keys between two distant legal parties. The processing speed of privacy amplification has a significant effect on the secret key rate of CV-QKD system. We report the high-speed parallel implementation of length-compatible privacy amplification algorithm based on graphic processing unit. Length-compatible algorithm is used to satisfy the security requirement of privacy amplification at different transmission distances when considering finite-size effect. We achieve the speed of privacy amplification over 1 Gbps at arbitrary input length and the speed is one to two orders of magnitude faster than previous demonstrations, which supports high-speed real-time CV-QKD system and ensures the security of privacy amplification.

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Xiangyu Wang, Yi-Chen Zhang, Song Yu, Hong Guo. 2018-05-07. High-speed Implementation of Length-compatible Privacy Amplification in Continuous-variable Quantum Key Distribution. https://doi.org/10.1109/jphot.2018.2824316

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