For SSL certificates we have a web-of-trust principle. If we are allowed to make alterations to the certificate format, are there viable ways to automatically or semi-automatically authenticate the certificate information is really about the owner without a CA? It's not an option to distribute keys in advance.
So far I came up with one-time passwords after an handshake making sure that it's for the purpose to send this OTP. Which will have to be sent back through a medium that allows verification, such as texting from a known cellphone number.
Are there any other methods?
Edit: This question was not specific and had terminology mixed around, which resulted in a good practice to counter this. If you are interested in my original question it's been reformulated here: Authentication methods without trusting 3rd parties unless explicitly indicated