Configuring Exchange SMTP Gateways at Microsoft is a new document available for download at the Microsoft site. It describes how Microsoft IT custom configures its SMTP servers to make its mail flow more securely and manageably.
Configuring a Simple Mail Transfer Protocol (SMTP) gateway to be secure as well as manageable can be a challenge. The e-mail team at Microsoft IT shares its experience with customers on configuring its Exchange Server 2003 SMTP gateways for optimal performance, security, and manageability.