Like its peers, Cloudflare’s is a recursive DNS service at the same time. As envisioned, in lieu of employing a centralized cache, the service takes advantage of a distributed one for better latency. It’s served by Cloudflare’s World Anycast Network and is out there publicly for everybody to utilize. https://eduardoqcnwh.isblog.net/anti-spam-filter-fundamentals-explained-43774829