It's no secret that Cloudflare has been a big proponent of TLS 1.3, the newest edition of the TLS protocol that improves both speed and security, since we have made it available to our customers starting in 2016.
Upgrading a security protocol in an ecosystem as complex as the Internet is difficult. You need to update clients and servers and make sure everything in between continues to work correctly. The Internet is in the middle of such an upgrade right now.
As I’m writing this, four DDoS attacks are ongoing and being automatically mitigated by Gatebot. Cloudflare’s job is to get attacked. Our network gets attacked constantly.
One thing we take pride in at Cloudflare is embracing new protocols and standards that help make the Internet faster and safer. Sometimes this means that we’ll launch support for experimental features or standards still under active development, as we did with TLS 1.3.
It may (or may not!) come as surprise, but a few months ago we migrated Cloudflare’s edge SSL connection termination stack to use BoringSSL: Google's crypto and SSL implementation that started as a fork of OpenSSL.