CDN’s or Content Delivery Networks help your users load your website or application faster by locating and caching static files, (for example images), physically closer to the user than your server.

Let’s say your website is hosted on a server somewhere. For those in Europe, that might be in London, Frankfurt or one of Amazons huge data centres in Ireland. For those in the USA, that might be East Coast or West Coast.

The speed of your website, or application depends on a number of things –

  1. How long it takes the server to process the request, compile the HTML and send it back to the user.
  2. How long it takes that HTML to get to the user.
  3. How long it takes the user’s browser to read this HTML and request the other files required to render the page.

This process usually doesn’t take too long – the server should be optimised to deliver the HTML quickly and the amount of data is relatively small.

At this point, the user needs to download all of the static files that support the page, including the css, javascript and the images. These generally make up the majority of the data to render the page to the user.

Because the amount of data is larger, the distance between the user and the server becomes more important, so CDNs store static files at many locations (nodes) around the globe.

Closer to the user means less distance for the information to travel, which means faster download speeds – simple.

Using the special AssetZen links, or integrating your systems with our API ensures that your images are served by a CDN and makes sure your images are optimised for delivery.