As with incoming connections, you can control outgoing connections to external SMTP virtual servers in several ways. You can do the following:
Require authentication for outgoing connections
Restrict concurrent connections and set connection time-out values
Configure message limits
Handle non-delivery, bad mail, and unresolved recipients
Set relay restrictions for message delivery
Each of these tasks is discussed in the following sections.
By default, SMTP virtual servers deliver messages to other servers without authenticating themselves. This mode of authentication is referred to as anonymous. You can also configure SMTP virtual servers to use basic authentication or integrated Windows authentication. ...