---
id:"kb-2026-00186"
title:"Content Delivery Network (CDN)"
schema_type:"TechArticle"
category:"computer-science"
language:"en"
confidence:"high"
last_verified:"2026-05-22"
generation_method: "human_only"
derived_from_human_seed: true
known_gaps:
  - "CDN market share and edge location counts change frequently; check provider documentation"
completeness: 0.88
primary_sources:
  - title: "Cloudflare CDN Documentation"
    type: "documentation"
    year: 2026
    url: "https://developers.cloudflare.com/cache/"
    institution: "Cloudflare"
    note: "One of the largest CDNs: 330+ cities, DDoS protection, WAF, edge computing"
secondary_sources:
  - title: "High Performance Browser Networking"
    authors: ["Grigorik, Ilya"]
    type: "book"
    year: 2013
    url: "https://hpbn.co/"
    institution: "O'Reilly"
    note: "Covers CDN architecture, TCP optimization, and latency fundamentals"
---

## TL;DR

A CDN is a geographically distributed network of edge servers that cache and serve content from locations closest to users, reducing latency and origin server load. Major CDNs: Cloudflare, Akamai, Fastly, Amazon CloudFront. CDNs handle ~75% of all web traffic.

## Core Explanation

CDN features: DDoS protection, SSL/TLS termination, WAF, image optimization, edge computing (Cloudflare Workers, AWS Lambda@Edge). Cache strategies: push (upload content) vs. pull (cache on first request). Anycast routing directs users to the nearest PoP. CDN edge locations: Cloudflare 330+ cities, CloudFront 600+ PoPs.

## Further Reading

- [undefined](undefined)