What is CDN(Content Delivery Network) and How it works?

Last Updated on July 2, 2019

Content delivery network commonly referred to as CDN is a large group of interconnected and geographically locations that enhances the deliveries of streaming and static content. The goal of CDN is to improve web performance by providing quick transfer of static assets for loading internet content including JavaScript files, HTML pages, stylesheets, video and images to transmit content and rich media to users’ Internet-connected devices.

As per the BuiltWith, 66% of the top 10,000 websites are making use of CDN, and this percentage has continually increased over the past decade due to an upsurge in the growth of digital content consumption. Making use of CDN is one of the most significant ways with reliability and high performance on a global scale.

The speed of the website is the first thing that creates an impression on the visitor’s mind, and that’s also perspective to judge you and your business. So, if the speed of the website will be slow, then user experience will be worst.

Many factors affect website speed, some of them are

• Slower database query response
• Code is not optimized
• Lower server configuration
• Web page assets (text, graphics, scripts, media files, software, documents, etc.)

Let’s deep dive to resolve each of the factors mentioned above

• Slower database query response

-> Query Optimization / Increase DB server configurations

• Code is not optimized

-> Optimize code / Reduce unused code

• Lower Server

-> increase server hardware configuration(RAM/Processor/Network)
->Decrease latency by implement distributed network ,geographically level.

• web page assets

-> CDN

Today almost every website is having dynamic content, i.e., CSS, JS, Images, Video, Flash, Animation files, etc.

Every other website ensures to deliver content to their end users with lower latency, CDN dispersed Content to different geographically distributed network locations, CDN server caching the contents of the page. Let’s take an example, our production server is hosted on Canada region and visitor user is trying to access the website, now based on server location user is getting all web content and user faces some content delivery network latency as you can see in below image that it’s taking 6 seconds to load all contents from website.

Now let’s move your website content to CDN, after making all required changes on the website, first time CDN Server will fetch data from the original server and then it stores this fetched data to nearest CDN points of presence. So, the data centers will be accountable for the communication with the visitors in their geographical vicinity. And the data centers will be also responsible to lessen the round trip time by bringing content closer to the visitors. Now the user is having low latency due to less caching servers and less distance, as shown in the below image that it reduces the time from 6 second to 2 second.

Reducing the loading time from 6 seconds to 2 seconds is indeed a huge improvement.

Listed are some of the most popular CDN providers.

1. Amazon CloudFront
2. https://cloud.google.com/cdn/
3. Cloudflare
4. Fastly
5. KeyCDN

Pratik Panchal View all post

I am working as Ruby on Rails Developer. and passionate about Cloud Computing. I am tech freak and like to prospect new technologies and their implementations.