Optimizing MDS Codes for Caching at the Edge

TL;DR

This paper develops an optimal caching strategy using MDS codes at the wireless edge to reduce backhaul load in heterogeneous networks, demonstrating significant performance improvements through convex optimization.

Contribution

It formulates the optimal cache placement as a convex optimization problem and analyzes its performance in heterogeneous network scenarios.

Findings

Optimal MDS-based cache placement reduces backhaul load.

Performance depends on file popularity, size, and base station capabilities.

Significant network performance improvements are achieved with the proposed scheme.

Abstract

In this paper we investigate the problem of optimal MDS-encoded cache placement at the wireless edge to minimize the backhaul rate in heterogeneous networks. We derive the backhaul rate performance of any caching scheme based on file splitting and MDS encoding and we formulate the optimal caching scheme as a convex optimization problem. We then thoroughly investigate the performance of this optimal scheme for an important heterogeneous network scenario. We compare it to several other caching strategies and we analyze the influence of the system parameters, such as the popularity and size of the library files and the capabilities of the small-cell base stations, on the overall performance of our optimal caching strategy. Our results show that the careful placement of MDS-encoded content in caches at the wireless edge leads to a significant decrease of the load of the network backhaul and hence to a considerable performance enhancement of the network.