honey@mailrus.cc.umich.edu (peter honeyman) (05/31/89)
steve, lemme take a crack at this. some time ago, there was discussion of the uucp "upper layer" protocol (S SY CY et al.) and its adverse effect on trailblazer throughput when the network traffic consists mostly of little files. one answer knocked around was batch smtp. others easily come to mind. what is the current state of the art in such systems? is anyone actually running a mail batching package? (would you care to describe it at the baltimore usenix work-in-progress session?) peter
david@ms.uky.edu (David Herron -- One of the vertebrae) (05/31/89)
The last "state of the art" which I know on BSMTP for UUCP is that
Greg Noel (do I have the right name? That guy at NCR in San Diego)
has a program for this.
Inputting BSMTP into the system is simple. You take my BSMTP decoder
from comp.sources.unix and use it, somehow. In RFC-976 it's sugested
that having the argument to rmail be "b-smtp" is all that's necessary
to trigger a BSMTP decoder. I've heard of people putting out an
"rbsmtp" program for this same sort of purpose.
Outputting BSMTP is strange because you don't know when the next
piece of mail is coming through. You'll there usually to be a
few pieces of mail in any one batch, up to some maximum size.
One way, which would work under MMDF but I'm not sure about other
systems, is to have the outgoing BSMTP channel be a background only
channel. Meaning that transactions can only be done by a background
daemon. Every so often the background daemon wakes up and queues/batches
the mail waiting in its queue. But this loses if the neighbor polls
just before the background daemon wakes up. It won't find anything in
the queue but if it had called a couple minutes later there would be
stuff waiting.
The program by Greg (right name?) remembered somehow the name of the
file in the UUCP spooling directory. When given a message to send out
it would go to that file and append the message to that file. Well, sort
of append because it has to back up one line so that it can precede
the QUIT command. But anyway, this works well because mail is always there
and can be added to at any time. But it's also bad because the name in
the spooling directory isn't very portable, "old UUCP" does it differently
from HDB which does it differently from Rick's UUCP which does it different
from all the versions of UUPC (& etc).
A vague possibility which just occurred to me is to make available
a "qbsmtp" command for remote sites. It takes an argument specifying
which host is requesting that BSMTP be batched up. (i.e. qbsmtp uunet)
Somehow this releases waiting mail for the particular host. This may
require two calls by the remote depending on how long it takes the
qbsmtp command to start and execute...
There's an underlying problem here that UUCP doesn't give good control
to the MTA level of the files in UUCP's control. MMDF, when it hands a
message off to UUCP, assumes the message is delivered. But when MMDF
is sending stuff via SMTP it has direct control, giving it more knowledge
over when the message is delivered &c. The same difference is true
with other MTA's..
As for a works-in-progress session? Well, I haven't done much work with
this even though I see the need for it to be done. If I gave a talk
it would be completely impromptu ... and besides, I'm not 100% sure
I'll be there yet.
--
<- David Herron; an MMDF guy <david@ms.uky.edu>
<- ska: David le casse\*' {rutgers,uunet}!ukma!david, david@UKMA.BITNET
<- By all accounts, Cyprus (or was it Crete?) was covered with trees at one time
<- -- Until they discovered Bronzechip@ateng.ateng.com (Chip Salzenberg) (06/02/89)
According to honey@mailrus.cc.umich.edu (peter honeyman): >... batch smtp ... others ... > >what is the current state of the art in such systems? is anyone >actually running a mail batching package? Smail 3 (still in alpha test!?) includes BSMTP support. I just wish Smail 3 were generally available. I wouldn't administer a local mail network without it, and I pity the novice postmasters trying to grok sendmail.cf... -- Chip Salzenberg <chip@ateng.com> or <uunet!ateng!chip> A T Engineering Me? Speak for my company? Surely you jest! "It's no good. They're tapping the lines."
steve@cdp.UUCP (10/29/90)
Apparently, honey posted a script to handle this
about a year ago. Anyone have a copy lying around ?
Steve Fram
Community Data Processing
{uunet, pyramid, hplabs, ...}!cdp!steve