SSL is the old name; TLS came to be because Microsoft refused to take a knee and use a Netscape protocol. But they were okay with using a Netscape protocol with a different name stuck to it. Go figure. Anyways, there's some documentation about SSL here.
gemini://rawtext.club/~nervuri/client-hello-mirror.gmi
gemini://tlsprivacy.nervuri.net/
tags #ssl #certificates #tls