# Wireless Caching Helper System with Heterogeneous Traffic and Random Availability

## TL;DR

This paper analyzes a wireless caching system with heterogeneous traffic and random helper availability, focusing on throughput and delay impacts of cache parameters, helper availability, and user request rates.

## Contribution

It introduces a comprehensive model for wireless caching with heterogeneous traffic and evaluates system performance considering helper availability and cache parameters.

## Key findings

- Helper availability significantly affects throughput and delay.
- Caching improves content delivery efficiency and reduces latency.
- System performance depends on packet arrival rate and cache size.

## Abstract

Multimedia content streaming from Internet-based sources emerges as one of the most high demanded services by wireless users. In order to alleviate excessive traffic due to multimedia content transmission, many architectures (e.g., small cells, femtocells, etc.) have been proposed to offload such traffic to the nearest (or strongest) access point also called "helper". The deployment of more helpers is not necessarily beneficial due to their potential of increasing interference. In this work, we evaluate a wireless system in which we distinguish between cachable and non-cachable traffic. More specifically, we consider a general system in which a wireless user with limited cache storage requests cachable content from a data center that can be directly accessed through a base station. The user can be assisted by a pair of wireless helpers that exchange non-cachable content as well. Packets arrive at the queue of the source helper in bursts. Each helper has its own cache to assist the user's requests for cachable content. Files not available from the helpers are transmitted by the base station. We analyze the system throughput and the delay experienced by the user and show how they are affected by the packet arrival rate at the source helper, the availability of caching helpers, the caches' parameters, and the user's request rate by means of numerical results.