CDN

A CDN, or Content Delivery Network, is a distributed network of servers positioned in data centers around the world that caches and delivers website content from the location nearest to each visitor. Instead of every request traveling to a single origin server that might be thousands of kilometers away, the CDN serves static assets like images, CSS, JavaScript, and video from an edge server in the same geographic region as the user. This dramatically reduces latency and page load times, especially for websites with an international audience.

The leading CDN providers include Cloudflare, AWS CloudFront, Fastly, and Akamai, each serving different market segments. Cloudflare has become particularly popular among web developers because its free tier provides CDN, DDoS protection, and SSL in one package. AWS CloudFront integrates tightly with the broader AWS ecosystem, making it a natural choice for applications already hosted on AWS. Fastly is favored for its real-time cache purging and programmable edge computing capabilities, which matter for dynamic content delivery.

The impact of a CDN on page speed and Core Web Vitals is substantial and measurable. By reducing the physical distance between the server and the user, a CDN can cut Time to First Byte by 50-80% for geographically distant visitors. This directly improves Largest Contentful Paint scores, which Google uses as a ranking signal. Beyond performance, CDNs provide resilience: if your origin server goes down or experiences a traffic spike, the CDN continues serving cached content, preventing complete outages. For any website that serves users across multiple countries or expects variable traffic loads, a CDN is not an optimization -- it is a baseline requirement.