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From: rhealey@digibd.com (Rob Healey)
Newsgroups: comp.unix.sysv386
Subject: Re: SYSV R4.0 High speed UUCP
Keywords: UUCP V.32 V.42bis PEP
Message-ID: <1991Feb21.223209.4257@digibd.com>
Date: 21 Feb 91 22:32:09 GMT
References: <1991Feb15.054602.913@jadpc.cts.com> <24318@netcom.COM> <1991Feb17.195353.25156@rwwa.COM>
Organization: DigiBoard Incorporated, St. Louis Park, MN
Lines: 22

In article <1991Feb17.195353.25156@rwwa.COM> witr@rwwa.COM (Robert W. Withrow) writes:
>Yes, and there is the rub.  My interpretation is that each modem
>manufacturer has implemented V.42/V.42bis slightly differently (this
>was the gist of a Byte review of these modems) leading to
>incompatabilities.  I know for a fact that I cannot do 9600 BPS UUCP
>using a Practical Periphials modem to a Telebit T2500 when using
>V.42(bis) LAP-M/compression.  If I turn off the V.42/bis stuff the
>transfer works OK.
>
	Try puttsing with the direction that compression is allowed on
	the Telebit side. You CAN turn off compression and just use
	LAP-M, this worked betwixed my T2500 at home and the MultiTech
	at work. The T2500 can also be told to do compression in both, one
	or neither direction. What I did in the end was switch to MNP 5 and it
	all just worked.

	Why use LAP-M when MNP works just as well? The only way you'll
	get 4x compression out of V42.bis is if you transmit zeros...
	You'd be surprised how well zero's compress... B^). In my
	practical experience, MNP 5 does just as well as LAP-M/compression.

		-Rob