From owner-freebsd-questions Mon Aug 9 21: 4:54 1999 Delivered-To: freebsd-questions@freebsd.org Received: from cc942873-a.ewndsr1.nj.home.com (cc942873-a.ewndsr1.nj.home.com [24.2.89.207]) by hub.freebsd.org (Postfix) with ESMTP id 7EE8214EB6 for ; Mon, 9 Aug 1999 21:04:49 -0700 (PDT) (envelope-from cjc@cc942873-a.ewndsr1.nj.home.com) Received: (from cjc@localhost) by cc942873-a.ewndsr1.nj.home.com (8.8.8/8.8.8) id AAA28584; Tue, 10 Aug 1999 00:03:53 -0400 (EDT) (envelope-from cjc) From: "Crist J. Clark" Message-Id: <199908100403.AAA28584@cc942873-a.ewndsr1.nj.home.com> Subject: Re: Mail server question In-Reply-To: <000201bee2dd$2e94b520$0201010a@cmr.net> from Mark Einreinhof at "Aug 9, 99 10:05:20 pm" To: montana1@home.com (Mark Einreinhof) Date: Tue, 10 Aug 1999 00:03:53 -0400 (EDT) Cc: freebsd-questions@FreeBSD.ORG Reply-To: cjclark@home.com X-Mailer: ELM [version 2.4ME+ PL40 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Mark Einreinhof wrote, > Ok, help me understand the difference in mail servers... > > Sendmail handles SMTP traffic, but doesn't handle POP. Is that correct? Does > Sendmail handle IMAP or is that an add on? Just like POP, IMAP is a separate protocol. You often get POP and IMAP from a single package, however. > If I install UW's IMAP software does that mean I have SMTP/POP/IMAP separate > from Sendmail, or does it mean I just added POP/IMAP to the server and > sendmail handles SMTP? Yes... Kinda. sendmail is a Mail Transfer Agent (MTA). sendmail is what gets email from your "site" to someone else's "site." Now how a user gets mail to their Mail User Agent (MUA) is up to the people at the other site. They might use POP or IMAP, or even just good ol' elm or pine reading straight off of a mailspool created by sendmail's local delivery. The UW IMAP package provides POP and IMAP. It does not really do SMTP. It is what a MUA (say fetchmail, Netscape, or M$ Outlook) would contact to grab mail from the server. When the MUA wants to send mail, it typically will use SMTP itself and go directly to the sendmail MTA for relaying. IMAP or POP is not involved in the sending of mail. Get it, got it, good. It seems complicated, but this is because each piece of software has a specific job to avoid each one from getting too bloated (well, sendmail...). Once you figure out what each does and how they fit together, it is quite simple. The alternative is making something that is meant to be an end-all-be-all mailserver that becomes a hopeless snarl, e.g. M$ Exchange. -- Crist J. Clark cjclark@home.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message