Caching Placement in Stochastic Wireless Caching Helper Networks: Channel Selection Diversity via Caching

TL;DR

This paper develops an analytical framework for optimizing probabilistic caching placement in wireless helper networks, balancing channel diversity and interference to maximize content delivery success.

Contribution

It derives closed-form optimal caching probabilities considering wireless fading, interference, and helper memory constraints, advancing caching strategies in stochastic networks.

Findings

Proposed caching placement outperforms existing strategies in simulations.

Derived closed-form solutions for optimal caching probabilities.

Validated effectiveness in both noise-limited and interference-limited scenarios.

Abstract

Content delivery success in wireless caching helper networks depends mainly on cache-based channel selection diversity and network interference. For given channel fading and network geometry, both channel selection diversity and network interference dynamically vary according to what and how the caching helpers cache at their finite storage space. We study probabilistic content placement (or caching placement) to desirably control cache-based channel selection diversity and network interference in a stochastic wireless caching helper network, with sophisticated considerations of wireless fading channels, interactions among multiple users such as interference and loads at caching helpers, and arbitrary memory size. Using stochastic geometry, we derive optimal caching probabilities in closed form to maximize the average success probability of content delivery and propose an efficient algorithm to find the solution in a noise-limited network. In an interference-limited network, based on a lower bound of the average success probability of content delivery, we find near-optimal caching probabilities in closed form to control the channel selection diversity and the network interference. We numerically verify that the proposed content placement is superior to other comparable content placement strategies.