It appears that Mike Hillyer via mailop <m...@mikehillyer.com> said: >So, before allowing access to submission service, Postfix consults IMAP server >(Dovecot in this case) to check if there is actually a >currently existing authenticated IMAP session from that IP address. Only if >such a session exists, connection is allowed and the client >may proceed to authentication attempt. Otherwise, the connection is >immediately rejected.
This is a very old idea. See https://en.wikipedia.org/wiki/POP_before_SMTP It's not clear who originally invented it. It may have been me. R's, John _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop