Overseas high -defense servers and CDN (content distribution network) are different services to improve website performance and security. They have some differences in functional and application scenarios:

　　Uses and positioning:

　　Overseas high -defense server: It is mainly used to prevent various network attacks, such as DDOS (distributed refusal service) attack. It focuses on providing high protection levels to ensure that websites can still maintain availability when facing large -scale attacks.

　　CDN: It is mainly used to accelerate content transmission and improve the loading speed of the website. CDN can obtain these resources from the positions closer to them by distributing the static resources of the website to the edge nodes around the world.

　　Defense mechanism:

　　Overseas high -defense servers: Provide professional protection services for various network attacks, including DDOS attacks, malicious reptiles, SQL injection, etc. It usually has stronger protection capabilities and can cope with complex network threats.

　　CDN: Provide a certain degree of security, mainly to reduce the pressure on the source server by decentralized traffic and cache, but does not focus on defense specific network attacks.

　　Acceleration mechanism:

　　Overseas high -defense server: Usually do not provide global content acceleration services, and its main responsibility is defense attack. It may be limited in acceleration.

　　CDN: Storage static resources through the edge nodes distributed around the world to accelerate the transmission of content. Users can obtain what they need from closer to them and increase access speed.

　　Content cache:

　　Overseas high -defense server: It is mainly used to handle dynamic content and protect source servers, and usually does not involve global distribution and cache of static content.

　　CDN: Through cache static resources, such as pictures, CSS, JavaScript, etc., these resources can be obtained by users more quickly and reduce requests for source servers.

　　cost:

　　Overseas high -defense servers: usually positioned as high security services, so the cost may be higher.

　　CDN: Provide relatively economic content transmission services, suitable for large -scale content distribution needs.

　　Sometimes the use of overseas high -defense servers and CDNs can be used to achieve the effect of comprehensively improving the performance and security of the website. For example, combining high -defense server and CDN services can provide more comprehensive protection and faster content transmission.