Cloudflare is an American company specializing in distributed reverse proxy services for websites. A disturbingly large portion of the world wide web is served from their network. Cloudflare is also one of the two most widely used providers of anycast DNS services (188.8.131.52 and 184.108.40.206) and they are the most used DNS over HTTPS service.
Cloudflare is in a prefect position to monitor a very large portion of all web traffic.
Cloudflare's headquarters are in San Francisco.
Public DNS servers
Cloudflares anycast DNS servers can be used by anyone. They are
- 220.127.116.11 and 18.104.22.168 on IPv4
- 2606:4700:4700::1111 and 2606:4700:4700::1001 on IPv6
Cloudflare offers free DNS hosting. Have have more than 12 million customers.
Cloudflare is very popular among website owners because they do provide several very real benefits. First of all, they do a lot of caching which offloads servers that are actually hosting a site. More importantly, Cloudflares network (AS13335) is large and well connected. Cloudflare is connected to over 230 Internet exchanges and they have direct peering with more than 580 different networks. Very few, if any, traditional server hosting companies have anything which comes close. A website using Cloudflares distributed reverse proxy network will feel (and actually be) faster for a very large part of the worlds Internet users.
AMP pages from web hosts behind Cloudflare are served directly from Cloudflares network.
Cloudflare suffered an outage which lasted a mere 27 minutes in July 2019. It was later revealed that it was caused by a invalid regular expression somewhere in the code. 12 million websites were unavailable during this half-hour long event.