# Blockchain-based Content Delivery Networks: Content Transparency Meets User Privacy

## TL;DR

This paper introduces a blockchain-based content delivery network (B-CDN) that enhances content transparency and user privacy, enabling decentralized management, improved user experience, and cost reduction for content providers.

## Contribution

The paper proposes a novel blockchain architecture for CDNs that ensures user privacy and creates an immutable content database for better user preference analysis.

## Key findings

- B-CDN improves user quality of experience.
- B-CDN reduces content delivery costs.
- The feature-based caching algorithm performs well on Movielens data.

## Abstract

Blockchain is a merging technology for decentralized management and data security, which was first introduced as the core technology of cryptocurrency, e.g., Bitcoin. Since the first success in financial sector, blockchain has shown great potentials in various domains, e.g., internet of things and mobile networks. In this paper, we propose a novel blockchain-based architecture for content delivery networks (B-CDN), which exploits the advances of the blockchain technology to provide a decentralized and secure platform to connect content providers (CPs) with users. On one hand, the proposed B-CDN will leverage the registration and subscription of the users to different CPs, while guaranteeing the user privacy thanks to virtual identity provided by the blockchain network. On the other hand, the B-CDN creates a public immutable database of the requested contents (from all CPs), based on which each CP can better evaluate the user preference on its contents. The benefits of B-CDN are demonstrated via an edge-caching application, in which a feature-based caching algorithm is proposed for all CPs. The proposed caching algorithm is verified with the realistic Movielens dataset. A win-win relation between the CPs and users is observed, where the B-CDN improves user quality of experience and reduces cost of delivering content for the CPs.