What is the function of Sitecore's Content Delivery Network (CDN)?

The function of Sitecore's Content Delivery Network (CDN) is primarily to distribute static resources geographically. CDNs are designed to cache and serve content like images, stylesheets, JavaScript files, and other static assets from locations that are closer to the end-users. By doing so, CDNs help reduce latency, lower load times, and improve the overall performance of a website. This geographical distribution allows for faster content delivery and enhances user experience, especially for a global audience.

In the context of Sitecore, utilizing a CDN also means that the primary application can offload the serving of static resources, which can lighten the load on the Sitecore instance and improve scalability as user traffic grows.

The other options do not accurately represent the primary function of a CDN. For instance, while hosting all Sitecore applications centrally might involve some elements of content delivery, it does not embody the specific geographical distribution aspect of CDN technology. Optimizing SEO for all pages is typically handled through other Sitecore features and best practices rather than through CDN functionality. Lastly, tracking user behavior is a separate concern and is generally managed through analytics and tracking tools, not directly through a CDN.