# Overview
IONOS Cloud [Content Delivery Network (CDN)](https://docs.ionos.com/cloud/support/general-information/glossary-of-terms#content-delivery-network-cdn) is a network of servers located across the IONOS Cloud global edge network to speed up the delivery of static and dynamic web content to users. CDN uses [Anycast routing](#user-content-fn-1)[^1] in IONOS Cloud's global backbone network infrastructure, comprising multiple highly available edge locations where the content is distributed, offering reduced latency, and high reliability of content loading on websites.
With CDN, users benefit from improved website performance. It provides the scalability to handle large spikes in traffic, making it ideal for websites and applications with a global audience. CDN offers advanced security features such as encryption, [DDoS Layer 7 protection](#user-content-fn-2)[^2], secure token authentication, and [Web Application Firewall (WAF)](https://docs.ionos.com/sections-test/guides/network-services/cdn/overview/web-application-firewall), making it a versatile choice for secure content delivery and safeguards against cyber threats. For more information, see [Features and Benefits](https://docs.ionos.com/sections-test/guides/network-services/cdn/overview/features-benefits) and [Use Cases](https://docs.ionos.com/sections-test/guides/network-services/cdn/use-cases).
The CDN accelerates content delivery by leveraging IONOS Cloud's global infrastructure and high-performance Points of Presence (PoPs) strategically located across major regions. These regions include: Germany (Berlin and Frankfurt), Spain, the United Kingdom, and the United States (US east and US mid regions). The network will continue to expand, bringing servers closer to your user base.
The CDN setup allows the administrator to create new CDN distributions and specify the origin servers for the CDN. The setup supports various origin types, such as S3 buckets, load balancers, and custom origins. For a CDN distribution, you can enable [SSL/TLS support](#user-content-fn-3)[^3] and manage these certificates to ensure a secure content delivery. CDN lets you configure up to twenty-five routing rules where geo-restriction can be managed on a per-distribution basis, and you can choose to enable WAF and Caching properties. You can configure and manage the CDN distributions through the DCD. For more information, see [DCD How-Tos](https://docs.ionos.com/sections-test/guides/network-services/cdn/dcd-how-tos).
## How does CDN work?
When a user sends a request for the first time to fetch content on your website, the user request is routed to the CDN edge server located closer to the user. The CDN requests content from the [origin server](#user-content-fn-4)[^4], transfers the static content from the webserver to its [cached memory](#user-content-fn-5)[^5], and sends the retrieved content to the user.
When a user requests the same data content the next time, the CDN retrieves the content from its cached memory and immediately delivers it to your website. When the content is cached in the edge server, the CDN provides it immediately with minimal or zero latency, thus improving the web application performance, and reducing data traffic.
The illustration shows how the user's request for content is managed efficiently by using CDN edge servers and the flow of content between the user, origin server, [CDN edge location](#user-content-fn-6)[^6], and cached memory. The overall CDN is built on top of the IONOS Cloud network infrastructure.
[^1]: A network addressing technique in which multiple devices or servers use the same IP address, with incoming requests directed to the nearest or most efficient instance based on geographic location or network performance.
[^2]: A layer 7 (application layer) protection that safeguards web applications and content delivery services against DDoS attacks.
[^3]: A method to securely transmit data between users and servers by encrypting traffic, ensuring authentication, and enabling HTTPS for secure, and trusted content delivery.
[^4]: A central source that stores and serves the original content, which the CDN caches and delivers globally to ensure faster user access.
[^5]: An edge server memory that temporarily stores frequently accessed content, enabling faster retrieval for user requests and minimizing repeated processing or fetching from the origin server.
[^6]: A strategically placed server that delivers cached content to users from the nearest geographic point, reducing latency and improving performance.