An Improved Lower Bound for Multi-Access Coded Caching

TL;DR

This paper derives a tighter lower bound on the optimal rate-memory trade-off for multi-access coded caching, improving understanding of the fundamental limits in systems where users access multiple caches cyclically.

Contribution

It introduces a new, improved lower bound for multi-access coded caching using non-cut-set arguments, surpassing previous bounds in accuracy.

Findings

The new lower bound is tighter than existing bounds.

The bound applies to systems with cyclic cache access.

It advances theoretical understanding of caching limits.

Abstract

The multi-access variant of the coded caching problem with $N$ files, $K$ users and $K$ caches, where each user has access to $L$ neighbouring caches in a cyclic wrap-around manner, is considered. A cut-set based lower bound on the optimal rate-memory trade-off of the multi-access coded caching (MACC) scheme is derived. Furthermore, an improved lower bound on the optimal rate-memory trade-off of the MACC scheme is derived using non-cut-set arguments. The improved lower bound is tighter than the previously known lower bounds for the same setting.