CDN – Basic Description and Setup Guide

If you have ever looked at the Google PageSpeed Insights tool or otherwise explored performance optimization, you know that there are many different ways to achieve faster delivery of your content: browser caching, script minification, image optimization, etc. Patrick Sexton, the author of the thorough Google Webmaster guidelines site, stresses that the content delivery network, a.k.a. CDN, is now fundamental to Internet success: “CDNs are becoming a defacto part of a webmaster’s toolkit, and even if you don’t get one now you will probably have to do so later.”

Sexton is of course not the only one who feels that way, and that’s reflected in a report on CDN trends, geographical analysis, and market predictions released by in March. The 196-page report, which details the in-depth findings of the research firm’s analysts, reveals how the CDN market will expand from a $3.7 billion industry in 2014 to a $12.2 billion industry in 2019. While the worldwide Compound Annual Growth Rate (CAGR) is phenomenal at 27%, the APAC region is particularly stunning in this sector, with a 38% CAGR forecast over the next five years.

What are CDNs & How Do They Operate?

A content delivery network, also called a content distribution network, is a distributed deployment of servers located in various data centers in disparate geographical locations. The CDN structure is designed to deliver content to the visitors of a site rapidly and with high availability. You may notice that the CDN is a similar concept to the public cloud, and most content delivery networks are now cloud-based. CDNs serve a sizable percentage of Internet content, such as web objects (e.g., graphics), downloadable objects (e.g., media files), applications (e.g., transaction software), and streaming content.

A CDN often operates as a form of software as a service (SaaS), which is a type of cloud computing. Content, as one copy or multiple, can exist on different servers in locations thousands of miles away. A user in a particular location requests content from a CDN hostname, and the DNS points to the best possible server. Factors that make the server ideal are the following, although location is touted the most highly (since it has a huge effect on latency, in turn impacting user experience and search engine optimization):

  • Geographical Location
  • Resource Availability
  • Cost of Delivery.

Setting Up Your CDN

Here is a quick setup guide (in the form of questions) from Sexton (mentioned above). We of course all want everything to be as simple and fast as possible, but he recommends setting aside an initial two hours for ideal integration of your site with the network, noting that it is well worth the effort: “A properly set up CDN will always outperform.”

What files are you serving with the CDN?

Typically a CDN will serve your webpage assets, such as images, JavaScript, and CSS files. You want those files on the CDN so that your assets are as close as possible to each user. Often, the HTML goes through your web host, while the assets go through your CDN.

How do you get your files onto the CDN?

Sexton points out that with some content delivery networks, it is not easy to perform this step. With strong CDN companies, you just supply simple information such as the URL of your site and some other basic descriptive information. As CDN’s are becoming more prevalent, they are also becoming much easier to use. Much of the process should be automated, particularly if you have a content management system (CMS) on your site, such as WordPress or Joomla.

How should you designate your URLs?

Once you’re hooked up to the CDN, your files will have different URLs. Sexton uses the example of a CSS file that is currently called “” Within a CDN, it might look something like this: “hyg375674355345scfd34/main.css.” That may seem shocking at first, but you don’t have to keep that name. Figure out a name that makes sense to you, such as “” Use the CNAME tool so that the new location of your CSS file is “”

Are your webpages calling the correct files?

This step can be challenging, but it’s simple with WordPress and other standard content management systems. You want the CMS to swap your files out with a caching tool, such as W3 Total Cache. Caching plug-ins are critical to page speed, and they also largely automate this step.

How do I test?

Typically a CDN will have a control panel that allows you to see how your files are being used. You can also go to a service such as webpagetest to check functionality in various regions.

Should you be concerned about search engine optimization (SEO)?

It’s reasonable to wonder whether adjusting the names of your files could damage your search engine rankings (even as the increased speed helps them). A high-quality content delivery network will account for that, such as Sexton’s example of a remote “robots.txt.”

Going Live

Although the above steps may sound somewhat complicated, it’s typically a matter of “set it and forget it” – as Sexton puts it, “The initial setup is the main task.” The Superb CDN will save your visitors substantial time, which translates to better engagement and higher conversion rates. Benefit from our 172 points of presence in 43 countries today: chat with an expert now.

By Kent Roberts

Image Credit: Success Creations