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From: johnl@esegue.segue.boston.ma.us (John R. Levine)
Newsgroups: comp.mail.uucp
Subject: Re: New UUCP Protocol (was: Re: Zmodem added to UUCP)
Message-ID: <1989Oct9.003603.3693@esegue.segue.boston.ma.us>
Date: 9 Oct 89 00:36:03 GMT
References: <1024@faatcrl.UUCP> <710@lakart.UUCP> <1029@faatcrl.UUCP> <688.252e37c2@simpact.com> <1032@faatcrl.UUCP>
Reply-To: johnl@esegue.segue.boston.ma.us (John R. Levine)
Organization: Segue Software, Cambridge MA
Lines: 26

In article <1032@faatcrl.UUCP> jimb@faatcrl.UUCP (Jim Burwell) writes:
>I think the answer would be to forget about 'g', and include Zmodem into 
>uucico's protocol list.  ...  Also, I think we would see a big throughput
>increase with the many PEP modems out there in Unix land.  Even though
>Telebits do all that funky spoofing, it still adds overhead to the
>transmission.  With Zmodem, there wouldn't be a need for spoofing.

Zmodem is undoubtedly a better protocol than 'g' for a full-duplex
transparent connection such as that provided by 2400 bps modems, 9600 bps
V.32 modems, or by packet switch networks.  PEP, though, is really a
half-duplex protocol, and fakes full-duplex by turning the line around.  That
means that the zmodem ACK packets cause a performance hit and spoofing would
still be a win.

If someone who actually understands the details of how Telebit's spoofing
works, and what sort of protocol they really use, that would be great.  PEP
uses a large number of very slow channels, and I don't know whether spoof
mode means that they use a few of the channels for the ACKs and the rest
for the data, or if they use bigger blocks and still turn the line around.

(Gee, Jim, I never had any trouble sucking down news from you using 'g'
spoof mode.)
-- 
John R. Levine, Segue Software, POB 349, Cambridge MA 02238, +1 617 492 3869
johnl@esegue.segue.boston.ma.us, {ima|lotus}!esegue!johnl, Levine@YALE.edu
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