A content delivery network or content distribution network (CDN) is a large distributed system of servers deployed in multiple data centers across the Internet. CDN’s goal is to server the content to end users with high performance and reliability. Azure CDN now supports Azure websites service which helps make your website perform faster and provides you’re with high availability. Azure CDN is designed for:
Better performance for your apps and services
The Azure Content Delivery Network (CDN) is designed to send audio, video, applications, images, and other files faster and more reliably to customers using servers that are closest to each user. This dramatically increases speed and availability, resulting in significant user experience improvements.
Designed for today’s web:
Azure CDN was specifically designed for the dynamic, media-centric web of today—and its users who expect everything to be fast, high quality, and always-on. Built on a modern network topology of large centralized nodes, Azure CDN is backed by massive storage and compute capacity within an agile cloud infrastructure.
How to create an Azure CDN for a Website
- Login to Azure Management portal
Click on New -> App Services ->CDN -> Quick Create to create a new CDN endpoint. Select the Website you want to enable CDN .
- Click on complete
Note that DNS changes with CDN takes 60 mins to take into effect before you site can be accessible with the CDN URL . If you website using HTTPS , you need to enable HTTPS for the CDN endpoint .To do this:
- Select CDN service from the left side menu
- Click on ENABLE HTTPS at the bottom toolbar
Once HTTPS is enabled , you can use your CDN endpoint for both HTTP and HTTPS protocols
To understand the performance improvements, I created a test site using Drupal CMS http://drupalsamplesite.azurewebsites.net/ without CDN and ran a 5 minute load test using Load Impact service. You can view the complete results of the test here
After adding a CDN endpoint for the same website, the page response time was reduced by almost 50%. You can view the complete results of the test with CDN enabled here
The metrics above are
- User load time which is the amount of time a simulated client has spent loading resources from the tested server. This value reports the actual load time as experienced by a typical user on your site, at different load levels.
- Client Active which represents the number of active clients in a test to generate the user load for your site
Overall, the average page load time without CDN 1.4 seconds which reduced to 0.49 seconds with CDN enabled. You can achieve optimal performance for your websites with Azure CDN.