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arXiv · 1405.7441

Key Capacity with Limited One-Way Communication for Product Sources

Jingbo Liu·Paul Cuff·Sergio Verdú
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Abstract

We show that for product sources, rate splitting is optimal for secret key agreement using limited one-way communication at two terminals. This yields an alternative proof of the tensorization property of a strong data processing inequality originally studied by Erkip and Cover and amended recently by Anantharam et al. We derive a `water-filling' solution of the communication-rate--key-rate tradeoff for two arbitrarily correlated vector Gaussian sources, for the case with an eavesdropper, and for stationary Gaussian processes.

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Jingbo Liu, Paul Cuff, Sergio Verdú. 2014-05-29. Key Capacity with Limited One-Way Communication for Product Sources. https://doi.org/10.1109/isit.2014.6875012

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