DeePref: Deep Reinforcement Learning For Video Prefetching In Content Delivery Networks

TL;DR

DeePref employs deep reinforcement learning to optimize video prefetching in Content Delivery Networks, adapting to changing user patterns and outperforming traditional methods in accuracy and coverage.

Contribution

This paper introduces DeePref, a novel DRL-based prefetcher for CDNs that adapts to workload variations and enables transfer learning across networks.

Findings

DeePref achieves 17% higher accuracy over baseline methods.

DeePref increases prefetching coverage by 28%.

Transfer learning improves accuracy by 30% in new networks.

Abstract

Content Delivery Networks carry the majority of Internet traffic, and the increasing demand for video content as a major IP traffic across the Internet highlights the importance of caching and prefetching optimization algorithms. Prefetching aims to make data available in the cache before the requester places its request to reduce access time and improve the Quality of Experience on the user side. Prefetching is well investigated in operating systems, compiler instructions, in-memory cache, local storage systems, high-speed networks, and cloud systems. Traditional prefetching techniques are well adapted to a particular access pattern, but fail to adapt to sudden variations or randomization in workloads. This paper explores the use of reinforcement learning to tackle the changes in user access patterns and automatically adapt over time. To this end, we propose, DeePref, a Deep Reinforcement Learning agent for online video content prefetching in Content Delivery Networks. DeePref is a prefetcher implemented on edge networks and is agnostic to hardware design, operating systems, and applications. Our results show that DeePref DRQN, using a real-world dataset, achieves a 17% increase in prefetching accuracy and a 28% increase in prefetching coverage on average compared to baseline approaches that use video content popularity as a building block to statically or dynamically make prefetching decisions. We also study the possibility of transfer learning of statistical models from one edge network into another, where unseen user requests from unknown distribution are observed. In terms of transfer learning, the increase in prefetching accuracy and prefetching coverage are [$30%$, $10%$], respectively. Our source code will be available on Github.