What Is A CDN (Content Delivery Network)?


A CDN (or Content Delivery Network) is a network of servers that delivers cached static content from websites and applications to an end user based on several factors including the geographic locations of the user, the origin of the static content, and a content delivery server. Essentially, what the job of a CDN is to get the content being requested by the user, delivered to the user as quickly as possible.

In order to fulfill this need the CDN utilizes technology standards like Anycast, lighttpd or nginx, and BGP to send the static content files to the network of servers that are dispersed throughout several strategic geographic locations around the world which then cache the contents of the file. Then once a user who visits a website their computer (browser) makes a request to the server to download the content for viewing. Now this is where a CDN comes into the play. If the website is running a CDN, the CDN will use Point of Presence (PoP) technology to deliver the content being requested by the user using the closest server to their location.

Additionally, a CDN will minimize the number of Internet hops needed to send the content to the end user. Of course, the fewer the hops, the faster the delivery and the faster the site loads.

I recently setup a CDN for BestTechie and I’m very pleased. The site definitely seems much faster. I’ll have another post explaining the uses of CDN’s including how I use it for BestTechie as well as the company I chose to go with it as my CDN provider.