Content Delivery in Erasure Broadcast Channels with Cache and Feedback

TL;DR

This paper characterizes the achievable data rates in a multi-user erasure broadcast channel with caches and feedback, proposing a scheme that leverages receiver side information for efficient content delivery.

Contribution

It introduces a new delivery scheme that exploits user caches and feedback to optimize content delivery in erasure broadcast channels, extending existing methods.

Findings

Achievable rate region depends on cache size and erasure probability.

The proposed scheme outperforms traditional broadcasting methods under certain conditions.

Extensions to centralized placement and multi-antenna channels are feasible.

Abstract

We study a content delivery problem in a K-user erasure broadcast channel such that a content providing server wishes to deliver requested files to users, each equipped with a cache of a finite memory. Assuming that the transmitter has state feedback and user caches can be filled during off-peak hours reliably by the decentralized content placement, we characterize the achievable rate region as a function of the memory sizes and the erasure probabilities. The proposed delivery scheme, based on the broadcasting scheme by Wang and Gatzianas et al., exploits the receiver side information established during the placement phase. Our results can be extended to centralized content placement as well as multi-antenna broadcast channels with state feedback.