The purpose of a CDN is to make websites faster by bringing the website content closer to the user. The distance between the user’s location and the webserver will directly affect how fast the website loads impacting latency (time which data requires to travel between a client and a server). The further a webserver or any other server is from a client, the more latency it will have.
CDN solves this problem by establishing a Point of Presence (PoP) which are placed at strategic geographic location around the world.
A PoP is made up of ‘Edge server‘ which cache the contents of the origin webservers. A CDN also reduces the cost of network bandwidth for origin webservers.
CDN provides content availability and redundancy. CDN can also improve the security of a website such as from a Distributed Denial of Service (DDoS) attack.
