Evolution of the MTA architecture: the impact of security

As the Internet matured, security became more important and formerly adequate designs became inadequate. One of the victims of the increased need for security was sendmail. This paper shows how its competitors improved on its design in response to the increased need for security. The designers of qmail and Postfix used well‐known patterns to achieve better security without affecting performance; these patterns can be used by the designers of other systems with an increased need for security. Copyright © 2008 John Wiley & Sons, Ltd.