A Content Delivery Network (CDN) is a geographically distributed group of servers — called Points of Presence (PoPs) — that work together to deliver web content (images, CSS, JavaScript, videos) quickly to users worldwide. Instead of every request travelling to your origin server, users are served content from the nearest PoP, dramatically reducing latency.
How a CDN Works
- A user in Tokyo requests an image from your US-based server.
- Instead of travelling across the Pacific, the request is routed to the nearest CDN PoP (e.g. Tokyo).
- If the CDN has the image cached, it serves it instantly (cache hit).
- If not (cache miss), it fetches it from your origin, caches it, and serves it to the user.
- Subsequent users in Tokyo get the cached version with minimal latency.
Benefits of Using a CDN
- Faster load times — Content served from nearby servers.
- Reduced origin load — The origin server handles fewer requests.
- DDoS protection — CDN absorbs traffic spikes across its network.
- Improved Core Web Vitals — Lower LCP due to faster asset delivery.
- High availability — If one PoP fails, traffic routes to another.
Popular CDN Providers
- Cloudflare, AWS CloudFront, Fastly, Akamai, Bunny.net