What is a CDN? What do I need to use CDN for?

CDN(Content Delivery Network) refers to the content distribution network, also known as the content delivery network. This concept began in 1996 and was put forward by a research group of Massachusetts Institute of Technology to improve the service quality of the Internet. In order to publish rich broadband media content on the traditional IP network, they proposed to establish a content distribution platform based on the existing Internet to provide services for websites, and set up a special CDN service company in 1999 to provide professional services for Yahoo. Because CDN is a network overlay optimized to speed up network access, it is vividly called "network accelerator".

CDN has the following main functions:

(1) saving the bandwidth of backbone network and reducing the bandwidth demand;

(2) provide server-side acceleration to solve the problem of server overload caused by large user visits;

(3) Service providers can use Web Cache technology to locally cache the Web pages and objects that users have visited, so as to realize the access of the same object without occupying the exit bandwidth of the trunk, and improve the corresponding time requirement for users to access Internet pages;

(4) It can overcome the problem of uneven distribution of websites and reduce the construction and maintenance costs of websites themselves;

(5) reduce the influence of "communication storm" and improve the stability of network access.