What is a Content Delivery Network (CDN)?

A Content Delivery Network (CDN) is essentially a geographically distributed network of proxy servers and their data centers. The primary purpose of a CDN is to provide high availability and performance improvements for delivering content to end-users on the internet. This is achieved by spatially distributing the service, which serves content to end-users with high availability and high performance. CDNs are used to efficiently deliver a wide variety of content such as web pages, images, videos, and other types of web assets.

The fundamental principles behind CDNs include reducing latency (the delay before a transfer of data begins following an instruction for its transfer), which is achieved by minimizing the physical distance the content travels between the server and the user. This is especially crucial for dynamic content, large file downloads, and streaming media. CDNs also work towards optimizing the Internet backbone, network hops, and through transmitting content over highly reliable and interconnected backbone networks.

CDNs operate by caching content in multiple geographical locations known as “points of presence” (PoPs). Each PoP contains a number of caching servers responsible for content delivery to visitors within its proximity. In essence, a CDN puts your content in many places at once, providing superior coverage to your users. For instance, when a user requests a webpage that is part of a CDN, the CDN will redirect the request from the originating site’s server to a server in the CDN that is closest to the user and deliver the cached content. This not only speeds up the delivery of content to users