Network and addresses
CDN
A worldwide server network that serves the site to a visitor from the nearest node.
A CDN (Content Delivery Network) keeps copies of images, scripts and pages on servers in different countries. A visitor gets them from the nearest one — the site loads faster and your server is under less load.
A site behind a CDN or protection (Cloudflare, DDoS-Guard) is visible only by that network's addresses — which is why the “Which hosting is a site on” check shows the protection, not the real provider.