What is a CDN?

CDN is the abbreviation of Content Delivery Network, that is the meaning of "contents distribution network". Generally speaking of the Cdn acceleration, generally refers to the Web site acceleration or user download resources accelerated.

The basic idea of CDN is to avoid the bottleneck and link that may affect data transmission speed and stability as far as possible, so that the content transmission is faster and more stable. By placing node servers across the network, a layer of intelligent virtual networks based on the existing Internet, the CDN system can redirect the user's request to the nearest service node according to the network traffic and the connection of each node, the load status and the user's distance and response time.

CDN's core purpose is to enable users to access the network, obtain the required content, solve the network congestion situation, significantly improve user access to the Web site response speed or user download speed.

From the above professional point of view, may be a lot of small white friends do not know what the CDN means, the following small series of easy to understand the introduction again.

CDN Simple, is accelerated, when a Web site to speed up the CDN, it gives users the feeling is to visit the speed of the site or download things faster than without the speed of acceleration, faster or download things faster.

Why is the Web site open CDN User access will be faster? Because CDN distributes the source station content to all the nodes in the whole country, shortens the user to view the object delay, enhances the user to visit the website The response speed and the website usability, solves the network bandwidth to be small, the user accesses the quantity, the dot distribution

In short, when the site opened CDN, users visit the site, not directly to the site of the original server, but a server distributed to your nearest server node, because the server close to you, so access speed or download speed will be faster.

Do you remember the previous introduction of the computer Pepsi network to set up DNS? Also mentioned in the DNS server address must fill out the nearest to your IP, which is the nearest principle, in fact, very good understanding, such as domestic visits to foreign sites why slow? The main reason is that the distance is too far, CDN's mission is to store the site content in the country and even the global CDN node, users visit the site, you can get the nearest CDN cached content, thereby enhancing access speed.