Content Delivery Network: An Overview

Short for Content Delivery Network, a CDN is a network of servers that delivers cached static content from websites and applications to an end user based on the geographic locations of: the user, the origin of the static content, and a content delivery edge server.

Stated a little more simply: the closer the CDN server is to where the user is, the faster the user gets the content.

A CDN utilizes technology standards like Anycast, lighttpd and BGP to transmit the static content files to a network of servers that are dispersed at different geographic locations around the world, caching the contents of the file.

When a user or website visitor requests a static file that is linked to a CDN, the CDN redirects the request from the originating site's server to a PoP (Point of Presence) that is closest to the user, then delivers that cached content. The CDN's edge servers minimize the number of internet hops needed to transmit the file to the end user. The CDN will also communicate with the originating server to deliver any content that has not been previously cached.

The fewer the hops, the faster the delivery. Simple.

So what does this mean for your business?

Speed. Content Delivery Networks like MaxCDN speed the delivery of static website and application content -- audio, video, Javascript, CSS and XML elements -- on both high and low traffic Web sites. CDNs also speed up applications suited for mobile phones, as well as SaaS that have global or specific geographic reach. Latency times with MaxCDN are less than 1ms.

Crash Resistance. CDNs protect sites and apps from big traffic swells, providing an added layer of security against DDosS attacks like the ones that bring Facebook, MySpace, Twitter and some US government sites to their knees from time to time. By having a CDN in place, you distribute the load to multiple servers instead of having 100% of the traffic go to your origin server.

Uptime. Is your site one of hundreds residing on your economy-priced webhost server? CDNs are the ideal solution for shared hosting and VPS (virtual private server) customers who compete for server resources. Even if a CDN takes one of their edge servers offline for maintenance, traffic to your website or application keeps flowing because those user requests are redirected to the next available location on the content delivery network.

Improved Visitor Experience. CDNs deliver lightning-fast load times, yet navigating through your website or application using a CDN is nearly transparent to the user. The only tip-off would be if the delivered URL is different than the requested URL. At MaxCDN, we give our customers the ability to use a custom or vanity domain name to mask the true CDN URL. This makes it nearly impossible for a user to tell any difference in terms of code structure that the static content on the page is coming from a different location other than the origin server.