Introduction to a CDN

Define a CDN as a distributed system that uses edge servers to minimize latency and reduce origin server load. Formalize the critical functional requirements, such as content retrieval and delivery, alongside non-functional requirements, including high performance, availability, and scalability.

We'll cover the following...

Requirements
- Functional requirements
- Non-functional requirements
Building blocks

A content delivery network (CDN) is a distributed system of servers strategically placed across various geographic locations to improve the speed and reliability of online content delivery. Instead of relying on a single origin server, a CDN uses a network of proxy servers positioned closer to the end users.

These proxy servers operate at the network edgeThe network edge is the zone where a device or local network interfaces with the Internet. and are often referred to as edge servers. By caching content near users, edge servers reduce latency, conserve bandwidth, and protect the origin server from traffic spikes.

CDNs minimize the physical distance data travels by storing copies of both ...