Cloudflare, Inc.

Sits in front of a very large share of the internet (CDN, DNS resolution via 1.1.1.1, DDoS mitigation); a Cloudflare outage (e.g. July 2025's widely-reported incident) takes down large numbers of unrelated sites simultaneously, making it one of the most consequential single points of failure to monitor. DNS resolver product (1.1.1.1) shares this same status page rather than getting a standalone DNS-subcategory entry.