wikipedia:SMTPS (it was TCP port number 465 using TLS)[1]
See also
- Mail, SMTP, submission, SMTPS, POP, IMAP, StartTLS, Exim, Postfix, IRedMail, Fail2ban, Dovecot, Roundcube, DKIM, SPF, DMARC, MX,
ssmtp, mailx, Swaks
↑ https://www.mailgun.com/blog/which-smtp-port-understanding-ports-25-465-587/
