From Fedora Project Wiki

MailServer

Present guide is targeted for small mailserver, serving domain with few clients.

Components

Normally mailserver will consist of several components:

  • MTA, message transport agent. This is the core of the mailserver, taking mail from clients and relaying/delivering towards destination host.
  • Sendmail
  • Postfix
  • Qmail
  • MDA, message delivery agent, responsible for placing arrived mail into proper mailbox, according to rules.
  • Procmail
  • MUA mail user agent, end user's interface for working with mailbox, reading and composing, submitting mail to MTA
  • kmail
  • evolution
  • mail
  • Self:pine
  • email security
  • selfsigned OpenSSL certificates

If you are behind the Self:NAT enabled Self:router the proper Self:portforwarding is also needed