Fundamental Limits of Caching: Improved Bounds with Coded Prefetching

Jesús Gómez-Vilardebó

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arXiv · 1612.09071

Fundamental Limits of Caching: Improved Bounds with Coded Prefetching

Jesús Gómez-Vilardebó

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Abstract

We consider a cache network in which a single server is connected to multiple users via a shared error free link. The server has access to a database with $N$ files of equal length $F$, and serves $K$ users each with a cache memory of $MF$ bits. A novel centralized coded caching scheme is proposed for scenarios with more users than files $N\leq K$ and cache capacities satisfying $\frac{1}{K}\leq M\leq\frac{N}{K}$. The proposed scheme outperforms the best rate-memory region known in the literature if $N\leq K\leq\frac{N^{2}+1}{2}$.

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Jesús Gómez-Vilardebó. 2016-12-29. Fundamental Limits of Caching: Improved Bounds with Coded Prefetching. https://arxiv.org/abs/1612.09071

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