Every time someone opens your website, their browser downloads images, stylesheets, scripts and fonts. If all of those files come from one server in one location, visitors who are far away wait a little longer for each of them. A content delivery network, or CDN, is designed to shorten that trip.
How a CDN works
A CDN is a network of servers in many locations. It keeps copies of your site’s static files, such as images, CSS and JavaScript, and serves each visitor from a location near them. Your main server still runs the website itself, but it no longer has to send every file to every visitor.
What a CDN can improve
- Loading time for distant visitors: files travel a shorter distance.
- Load on your server: fewer requests reach your hosting, which helps during busy periods.
- Consistency: visitors in different regions get a more even experience.
- An extra layer in front of your site: many CDNs can filter some unwanted traffic before it reaches your server.
When a CDN makes sense
A CDN is most useful when your visitors are spread over a wide area, when your pages carry a lot of images or media, or when you expect traffic peaks, for example during a campaign or a seasonal sale. Online stores, media-rich sites and businesses serving customers across the United States usually notice the difference.
If your audience is mostly local and your pages are light, a well-configured server with good caching may already cover most of what you need. In that case a CDN is a nice extra rather than a priority.
A CDN works best together with caching
A CDN and server-side caching solve different parts of the same problem. Caching makes your server prepare pages faster; the CDN delivers the files closer to the visitor. When they are configured together, with sensible cache rules and a clear way to refresh content after updates, you get the benefit of both. That is how we set it up as part of our CDN and caching and optimization services.
Things to keep in mind
- After changing content, cached copies may need to be refreshed. A good setup handles this automatically.
- Pages for logged-in users, shopping carts and checkouts are usually excluded from caching.
- A CDN does not replace a well-built site. Large images and heavy scripts still benefit from optimization.
Wondering whether a CDN would help your site? Contact our team and we will take a look at your setup together with you.
CDN features and coverage depend on your plan and are defined in your service agreement.