Content Delivery Network (CDN)
A Content Delivery Network (CDN) is a system of geographically distributed servers that work together to deliver website content — such as images, scripts, videos, and HTML — to users from a server that’s physically closer to them.
The main goal of a CDN is to improve website speed and performance by reducing the distance data has to travel. Instead of loading everything from your website’s main server (called the origin server), a CDN stores cached copies of your content in multiple locations around the world. These are called edge servers.
When a user visits your site, the CDN automatically delivers content from the nearest server, ensuring faster load times and a better user experience.
How a CDN works
Let’s say your website is hosted in London, but someone in Tokyo visits your site. Without a CDN, their request has to travel all the way to London and back, which can cause delays. But with a CDN, your content is also stored on a server in Tokyo (or nearby), so the user gets the content much faster.
This is especially helpful for global websites, large media files, and high-traffic sites.
Key benefits of using a CDN
- Faster website loading times
Content loads more quickly because it’s served from a server that’s closer to the user. - Improved user experience
Faster pages lead to lower bounce rates, longer visit durations, and higher conversion rates. - Better SEO performance
Site speed is a confirmed Google ranking factor. A fast-loading site improves crawlability and user engagement. - Reduced server load
Your main server handles fewer requests because the CDN distributes traffic across its network. - Increased reliability and uptime
If your origin server goes down, the CDN can often serve cached content in the meantime. - Enhanced security
Many CDNs offer protection against DDoS attacks, SSL encryption, and secure token authentication.
Examples of popular CDNs
- Cloudflare
- Akamai
- Amazon CloudFront
- Fastly
- Google Cloud CDN
Does a CDN host your website?
No — a CDN is not a web host. It works alongside your existing hosting provider by delivering copies of your content from edge servers. Your origin server still stores and manages your full website.
In summary, a Content Delivery Network (CDN) is a powerful tool for speeding up websites, improving SEO, and providing a better experience for users around the world. If your site serves a global audience or relies on fast, secure content delivery, a CDN is an essential part of your web infrastructure.