Path: utzoo!mnetor!uunet!husc6!rutgers!topaz.rutgers.edu!ron
From: ron@topaz.rutgers.edu (Ron Natalie)
Newsgroups: comp.mail.misc
Subject: What is MMDF
Message-ID: <17011@topaz.rutgers.edu>
Date: 13 Dec 87 17:12:26 GMT
References: <3047@phri.UUCP> <7807@g.ms.uky.edu> <540@ncrcan.Toronto.NCR.COM>
Organization: Rutgers Univ., New Brunswick, N.J.
Lines: 36

MMDF is the Multichannel Memo Distribution Facility.  This was originally
developed at the University of Delaware on a PDP-11/70 running some early
(V7?) unix.  One of the original uses for this system was for the DARCOM
(Army) PACE message server.  Principal author at the time was Dave Crocker.

MMDF consists of multiple delivery channels.  These channels each deal
with a different type of mail delivery.  The SMTP channel handles mail
on the internet, the UUCP channel through UUCP, etc...   Two specialized
channels are the Phonenet and local channels.   Phonenet is a special
machine-to-machine mail transfer protocol that runs over dial-up phone
lines.  Many people mistakenly refer to this channel as MMDF, but MMDF
is the overall system including all the channels.  Another channel, the
local channel, delivers mail into individual mailboxes on the local
machine.

Various "user agents" read the mailbox files and interact with the
rest of MMDF using a binary protocol (implemented as a subroutine
library) over pipes.  In addition to a sendmail emulator, there
are interfaces to a MM-like mail reader (msg) and various composing
programs.

MMDF has undergone a lot of change in the past seven years.  Development
work proceded at the University of Delaware along with Johns Hopkins
University and the Ballistic Research Laboratory.  Doug Kinston was
primarily involved with the core work.   MMDF was selected early on
to be used to form CSNET and a majority of the support for MMDF comes
from there.   The phonenet slave was tranlated into Pascal and has grown
into a large (primarily VMS) product called PMDF.

The basic answer is that both sendmail and mmdf have their limitations
(I don't like either).  The user interfaces from MMDF are very nice, but
the way that the various channels and user interfaces interoperate are
rather obscure.  Configuration is somewhat easier than with sendmail,
but not as rich in what you can do.

-Ron