> We might as well extend it by having recipient public keys available via DNS records directly (or DNS specifying how to fetch them using some other protocol)

> We might as well extend it by having recipient public keys available via DNS records directly (or DNS specifying how to fetch them using some other protocol) and encrypting the contents of the e-mail as well. That's just OpenPGP. There's even an OPENPGPKEY DNS record type. We all know how that went. It requires users to know what public keys are.