*BSD News Article 19179


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From: newton@cleese.apana.org.au (Mark Newton)
Newsgroups: comp.os.386bsd.bugs
Subject: Re: Problems with patchkit 0.2.4
Date: 5 Aug 1993 07:06:01 +0930
Organization: cleese.apana.org.au public access UNIX
Lines: 34
Message-ID: <23pa4i$47b@cleese.apana.org.au>
References: <1993Jul25.220104.13519@fcom.cc.utah.edu> <BLYMN.93Jul28182459@siren.awadi.com.au> <1993Jul29.032615.9906@fcom.cc.utah.edu>
NNTP-Posting-Host: localhost.apana.org.au

In article <1993Jul29.032615.9906@fcom.cc.utah.edu> terry@cs.weber.edu (A Wizard of Earth C) writes:
>In article <BLYMN.93Jul28182459@siren.awadi.com.au> blymn@awadi.com.au (Brett Lymn) writes:
>>Why buy MNP? IMHO it has too many problems to be worth it.  Apart
> ^^^^^^^^^^^
>>from, as you correctly state, the implementation varying between
>>manufacturers (I have experienced some MNP5 modems not talking to each
>>other at all) but also MNP will happily compress the data irrespective
>>of whether the data size is increased by the compression or not.  Much
>>better to get a v.42bis modem, they seem more reliable (from my
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>experience) and do not try to compress uncompressible data.  Besides
>>from what I see of the modem market MNP is a bit passe most high end
>>ones support v.42bis.  As for in-band flow control, I have an option
>>on my modem to turn it off, I have done so.
>
>Ask yourself "What standard do they use in v.32-BIS and v.42-BIS modems to
>do their compressing?".  This statement actually becomes kinda funny.

Bzzzt!

v.42 uses LAP-M for error correction; v.42bis uses BTLZ in conjunction 
with LAP-M for compression.

Neither of them make use of MNPx.

MNP protocols are proprietry, so they're hardly the correct choice as
a CCITT v.* standard, eh?

   - mark
-- 
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I tried an internal modem,                newton@cleese.apana.org.au
     but it hurt when I walked.                          Mark Newton
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