A content delivery network (CDN) refers to a geographically distributed group of servers which work together to provide fast delivery of Internet content.
A CDN allows for the quick transfer of assets needed for loading Internet content including HTML pages, javascript files, stylesheets, images, and videos.
The popularity of CDN services continues to grow, and today the majority of web traffic is served through CDNs, including traffic from major sites like Facebook, Netflix, and Amazon.
When a user makes a request it is routed to the nearest CDN edge server, which significantly reduces the latency.
A Content Delivery Network allows all users, no matter the geographical location, to have fast loading content for an unquestionably improved experience.
A properly configured CDN may also help protect websites against some common malicious attacks, such as Distributed Denial of Service (DDOS) attacks.
According to BuiltWith, 66% of the top 10,000 websites are using a CDN (November 2018).
This percentage has continually increased over the last 10 years due to the large growth of digital content consumption and high user expectations.
Utilizing a Content Delivery Network is one of the most effective ways to deliver content with high performance and reliability on a global scale.
In fact, a study done by the University of Nebraska found that the tolerable waiting time for information is approximately only 2 seconds.
How does a CDN work?
At its core, a CDN is a network of servers linked together with the goal of delivering content as quickly, cheaply, reliably, and securely as possible. In order to improve speed and connectivity, a CDN will place servers at the exchange points between different networks.
These Internet exchange points (IXPs) are the primary locations where different Internet providers connect in order to provide each other access to traffic originating on their different networks.
By having a connection to this high speed and highly interconnected locations, a Content Delivery Network provider is able to reduce costs and transit times in high-speed data delivery.