What is a CDN?
A content delivery network, or CDN, uses distributed servers to deliver website resources. It can serve suitable cached content closer to visitors and reduce repeated work at the original server. A CDN is not automatically the place holding your complete website, database or customer records, and it is not a backup service.
Useful context
- Ask whether your hosting platform already includes a CDN.
- Identify the supplier responsible for its configuration and cache rules.
How it works
Understand the original source
The original website service is often called the origin. A CDN may obtain material from it and reuse suitable responses. If the origin is broken, some cached pages might remain visible while forms or uncached pages fail. That is why a working homepage is not a complete availability test.
Know what should not be shared
Public images and styles are different from a personal order page or private account response. Cache rules must respect those differences. Ask the developer how customer-specific pages are protected rather than enabling a broad cache-everything option to chase a speed score.
Keep publishing and cache updates connected
After a content change, the CDN may need to refresh its stored version according to the site’s setup. If visitors see an old image, record its page and timing. Clearing your own browser cannot necessarily refresh what the CDN serves to everyone else.
Compare real customer outcomes
Use normal mobile and desktop journeys to check loading and function. A CDN may help delivery performance, but heavy images, slow applications and third-party scripts can still matter. Keep a record of who manages DNS, the origin and CDN so fault reports reach the right place.
What to check
- You know whether a CDN is already part of your hosting.
- Private pages have suitable cache controls.
- Content updates and key forms are verified separately.
Sources and further reading
Platform features can change. Check the provider’s current guidance before changing a live service.