The full name of CDN is Content Delivery Network. CDN is a new network architecture added to the existing Internet. By deploying edge servers and using load balancing, content distribution, scheduling and other functions, users can access the required content nearby, thereby solving website congestion and improving user access response speed.
　　II. CDN Acceleration Principle
　　CDN acceleration technology mainly adds a mirror cache layer between the user and the source server to guide the user's access request to the mirror cache node instead of directly accessing the source server.
　　During the CDN acceleration process, the global load balancing DNS resolution server will guide the user's access request to the cache server with the closest route, the closest location and the lightest load according to the user's source IP address, so as to achieve the best matching effect.
　　CDN Acceleration Technology
　　1. The user enters the domain name of the website to be visited www.xxxx.com in the browser and initiates a domain name resolution request to the local DNS.
　　2. The local DNS checks whether there is an IP address record of www.xxxx.com in the cache. If there is, it will be returned directly to the end user; if not, the website will be authorized to query the DNS.
　　3. The website DNS server resolves and finds that the domain name has been resolved to CNAME: www.xxxx.com.c.xxxx.com.
　　4. The request is directed to the CDN service.
　　5. The CDN performs intelligent resolution of the domain name and returns the IP address of the CDN node with the fastest response speed to the local DNS.
　　6. The user obtains the IP address of the CDN node with the fastest response speed.
　　7. After obtaining the IP address of the best node, the browser sends an access request to the CDN node.
　　CDN acceleration effect
　　(1) Reduce bandwidth demand by saving backbone network bandwidth;
　　(2) Provide server-side acceleration to solve server overload problems;
　　(3) To achieve full network coverage across operators and regions;
　　(4) It can overcome the problem of uneven distribution of websites and reduce the construction of websites themselves;
　　(5) Ensure the security of your website and prevent the website from being attacked maliciously.
　　FAQ
　　Q1: What is the difference between CDN and cloud security?
　　A1: CDN focuses on accelerating content delivery, while cloud security focuses on protecting websites from various cyber threats. The two can be used in combination to provide a more comprehensive website performance and security solution.
　　Q2: Do all websites need to use CDN and cloud security?
　　A2: Not all websites need to use CDN and cloud security. For websites with less traffic and low security requirements, CDN and cloud security may not be necessary. But for websites with large traffic and high security requirements, using CDN and cloud security can bring significant benefits.
　　Q3: How to choose the right CDN and cloud security service provider?
　　A3: Choosing the right CDN and cloud security service provider requires considering multiple factors, such as coverage, performance, security features, ease of use, cost, etc. It is recommended that you evaluate and choose according to your own needs.