Curated port reference

Port 465: SMTP submissions

SMTP submissions commonly uses port 465 over TCP. Review its purpose, traffic direction and operational security considerations.

465TCP

SMTP submissions

Authenticated email submission using implicit TLS.

Typical use

Mail clients sending outbound messages through a submission service.

Traffic direction

Client to server

Security considerations

Require authentication, modern TLS and anti-abuse controls; do not configure it as an unauthenticated relay.

SmtpEmail