I want to know exactly how does CDN work and how to set it up. Is there any documentation or guide available for it? If yes, then please share the URL.

I am not sure you can just implement it your self. We work with www.akamai.com for a few fortune 500 clients that requested.

but CDN is a series of server set up around the world that contain copies of the website or content, (video, etc) -
The capacity sum of strategically placed servers can be higher than the network backbone capacity. -

in even more simple terms it improves performance

It's certainly something you can setup yourself on a small scale, e.g. a few geographically distributed servers, with geoIP aware DNS.

It's certainly something you can setup yourself on a small scale, e.g. a few geographically distributed servers, with geoIP aware DNS.

Yep, that should be the simple side of it. If you are looking to offer it to customers, you may need a lot more development.

Been there done that :cool:

CDNs of old only handle static files. Akamai can accelerate dynamic content as well though some advanced optimization techniques.

In its most basic form it acts like any cache does.

Static files that are been requested multiple times are stored closer to the clients.

In basic CDN will cache the images and will distribute the server across the locations.

How do you redistribute databases that are updated every second? ;-) That is the tricky part.