Content Delivery Network (CDN) Primer

Have you ever wondered in this age of digital WebSphere with tons of online video, images being shared across the netizens of the globe, where increasingly news and publishing organizations delivering content to multiple channels (web and mobile) and more people are engaging in online commerce then ever; how does the enterprises ensure a smooth and efficient delivery of both static and dynamic content to the end users? A part of that answer is Content Delivery Networks or more commonly CDNs which are now days the most common ways to delivery digital content to end users.

Now what exactly is a CDN? CDN or Content Delivery Network is a huge mesh or web of strategically places edge server which tries to localize the content based on the location of end users requesting for content there by reducing the latency and increasing the throughput of the content delivery. Akamai which is a leader in CDN space has their servers located all over the globe which tries to cache the content of the providers (which utilizes Akamai's network) and then based on some intelligent algorithm Akamai chooses the geographically closer server which will serve a particular content object to the end user.

Check out the following diagram of an Akamai CDN network

Another interesting diagram of a CDN layout

Some other major CDN vendors are listed here

Some of the major corporates also build and own their own private CDNs in addition to subscribing to a pure CDN vendor. Based on the nature of the content (entitled and public) they can choose to use either of them.