CDN is a computer networked system that connects to each other over the Internet and delivers music, pictures, videos, applications, and other files to users faster and more reliably with the server closest to each user.
What is CDN?
With the development of internet, users pay more and more attention to the browsing and effects of websites when using internet.However due to of the surging number of internet users and long routes of network access, the quality of users access is severly affected. Especially when the link between user and the website is bursted by large traffic data. poor quality of access is an urgent problem to be solved in areas where number of users in remote areas is rapidly increasing. How can we make high quality to users everywhere and minimize the resulting costs and pressure on web site management? Content Develivery Network was born.
CDN is computer networked system that connects of each other via internet to deliver music,pictures,videos,application and other files to users faster and more reliable using the server closest to each user to provide high performance,Scalibility and low cost of network content to the user.
The total capacity of the content delivery network can be larger than the maximum bandwidth of a single backbone. This allows content distribute networks to carry more users than traditional single servers.In other words, if a 100Gbps server is put in a data center with only 10Gbps bandwidth, it can only play a 10Gbps payload. However, if you put ten sites with 10Gbps, the entire system can carry capacity of 10 * 10Gbps.At the same time, moving servers to different locations reduces the amount of traffic that is interconnected, which in turn reduces bandwidth costs. The actual number of nodes will affect the effectiveness of the CDN.
Another benefit of content distribution networks is the need for remote backup. When a server fails, the system will invoke server services from other nearby locations, providing nearly 100% reliability.
The use of CDN greatly simplifies the system maintenance workfload of the website. The site maintainer simply inject the website content into CDN system and distributes the CDN through the servers in various physical locations for distribution across the entire network, thereby realizing cross-carrier and cross-platform geographical user coverage.Becuase CDN pushes the content to the edge of the network, a large number of user accesses are scattered around the edge of the network.[https://yq.aliyun.com/articles/67298?spm=5176.10058615.846063.8.UKp19q]