"'Neither rain, nor sleet, nor snow...' SMTP (Simple Mail Transfer Protocol) gateways are the ubiquitous workhorses of the Internet today. People expect e-mail to be reliable and quick, so SMTP gateways always have to be highly available and work under a heavy-duty cycle. And now with the growing crush of spam showing no signs of abating, SMTP gateways are asked to be secure, as well as perform a host of other functions beyond basic 'store-and-forward' mail relaying.
"Using Linux as the platform for this part of your network infrastructure makes good sense. The Linux kernel and file system can run unattended for years. Linux can easily be locked down to serve this single purpose, and because the tradition of SMTP mail is deeply-rooted in open systems, there are several freely available, high-quality MTA (mail transfer agents) available for your Linux boxes..."
