Remote Domain
All domains that are not local are known as remote domains, and e-mail addresses with remote domain names are referred to as non-local addresses. Microsoft SMTP Service looks up remote domains in DNS. If you want to set unique delivery requirements for a specific remote domain, you can add a remote domain and configure it accordingly.

For example, you can add a remote domain and require that Microsoft SMTP Service always use Transport Layer Security (TLS) when sending messages to the domain. Or you can change the routing so that messages sent to one remote domain are routed to another remote domain.

To designate a domain as a remote domain, select the Remote Domain check box. To designate a local domain, clear the Remote Domain check box.