First acquaintance with CDN

Baidu general science ：CDN The full name is Content Delivery Network, The content distribution network .CDN It is an intelligent virtual network based on the existing network , Rely on edge servers deployed everywhere , Load balancing through the central platform 、 content distribution 、 Scheduling and other functional modules , Let users get the content they need nearby , Reduce network congestion , Improve user access response speed and hit rate .CDN The key technologies are content storage and distribution technology .

Why is there CDN？

Browser sends request to server , There are many nodes in the middle , When the browser is too far away from the server , Packet loss may occur during the transmission of the request 、 Blocking and so on , Therefore, multiple servers will be established in various places , Thus reducing the number of nodes between requests .

The edge server is the server closest to the user ,CDN It can handle static content and dynamic content , When the browser requests static content, it can directly return , When dynamic content is requested, the source server is needed .

Establish multiple CDN The server , Using load balancing technology , If overloaded, switch to other CDN On , guarantee CDN Safety and reliability of . Through anycast communication , These multiple CDN Have the same IP Address , By the nearest CDN Provide services . So when users visit , In fact, we will arrive first CDN Load balancing server

Reference material ：
b Stand technical egg teacher ： When CDN？