The SMTP AUTH functionality of SMG provides the ability to elevate SMTP client privileges based on their authenticated state. This allows for tiered mail delivery options based on the knowledge of access credentials by an incoming SMTP client connection.There are a multitude of ways, reasons and goals that SMTP authentication can used for, depending on the needs and layout of an email system.Without any configuration. SMTP AUTH does not provide any inherent advantages to a client that logs in to the SMG server. The privileges that are afforded to authenticated users are provided through various configuration parameters that link to the authenticated state of the SMTP session. how the authentication service is used is entirely dependent on the needs of each individual mail system. SMG does not dictate which privileges any user might receive after authenticating. Use this guide to determine what SMG can provide to authenticated users, and configure your system according to your needs.