The Content Delivery Network (CDN), or content delivery network, is a group of interconnected servers that provide fast delivery of Internet content. CDN is used to improve site rendering speed and performance. Subsequently, this is what allows you to reduce the loading time of the web page.
Content Delivery Network helps to speed up website loading using:
- automatic redirection of the client to the geographically closest server;
- minimizing and compressing files, respectively reducing the amount of data transferred;
- optimization of the software used;
- allowing a false TLS startup (for sites using TLS/SSL certificates).
CDN speeds up the loading of a wide variety of file types, including HTML pages, javascript files, images and videos. In addition, a properly configured CDN protects websites from hacker attacks, including DDoS attacks. The Content Delivery Network also optimizes data transfer processes between the client and the server and copes with various types of Internet failures and congestion.
How the Content Delivery Network (CDN) works
The main feature of CDN operation is the geographical diversity of the server location: the client, opening a web page, automatically connects to the nearest one. It is the reduction of the physical distance between the user and the server that speeds up the process. The servers themselves are located in Internet exchange points (IXPs) – data processing centers that provide CDN connection to high—speed traffic.
Users connected to different servers see the same information on the web page. This is because modern CDNs host copies of the required content on servers around the world.
Reducing the distance between the server and the client also allows large international companies to save on traffic. Storing files on local servers is much cheaper than constantly sending traffic across the ocean.
Unlike a web host, CDN does not host content. However, CDN helps cache content, which improves site performance: this is a difficult task for traditional hosting services.
How to understand that you need a CDN
- You have users in different countries or cities that are very far from each other.
- Most of your customers live far from the location where the company’s servers are located.
- Heavy files (for example, long videos) are published on your web pages.
But it is worth noting that in some cases, CDN costs are unnecessary: for example, if you have a local business or, conversely, it is impossible to determine the geolocation of the target audience of users.