Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!ucsd!casbah.acns.nwu.edu!squishy
From: squishy@casbah.acns.nwu.edu (Shishin Yamada)
Newsgroups: comp.sys.mac.comm
Subject: Re: Slow transfer rate on Telebit
Message-ID: <1991Mar17.063612.7712@casbah.acns.nwu.edu>
Date: 17 Mar 91 06:36:12 GMT
References: <13477@darkstar.ucsc.edu> <269@raysnec.UUCP>
Organization: Northwestern University
Lines: 42


	I have a Mac IIsi with a Practial Peripherals 9600SA (used to be
attached to my SE/30). I've encountered a lot of problems with file
transfers with our Sun Sparc station and finally resolved a lot of them
(some fixes were permanently installed by the sys admin). I found out very
quickly that Kermit seems to be the slowest transfer protocol of all. Right
now I typically use Zmodem because it is quick and dirty. X and Y modem
are also good protocols, but I optimized my setup for Zmodem. If you have
similar setups, you might have similar problems, is all I can say.

	I don't know exactly why your Kermit transfers are at only 3% of
true value. That is odd. I wouldn't know how that would happen, other than
maybe you have a speed bottleneck somewhere. I have a max transfer rate of
38,400 bps, but realistically I only get up to 9600 bps due to a speed
bottleneck imposed on our system. Our system is set up through a dial-in
unit that is connected to a gateway that operates at only 9600 bps, so in
my case I often see 25% efficientcy (25% at 38,400 bps = 9600 baud) and
this is normal. I've complained to the sys admin to speed things up at our
university and he said 'it was in the works.'

	In our BSD 4.2 unix, there are nice features of X/Y/Zmodem that are
implemented. If you have access to these and your transfers are hanging up
on you it could be because of the Xon/Xoff handshaking going on. This
happens cheifly with MacBinary files. Text files don't pose problems to
software handshaking, and don't barf. If this is the case, I think there is
a command called Zmodem -e <filename>. The -e option will Escape all
Xon/Xoff characters. This worked for me, but slowed transmissions. Later,
the sys admin changed this.

	I know this isn't much, but I hope it helps.

 
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Shishin "Squish" Yamada                    |\/\/\/|
 squishy@casbah.acns.nwu.edu  /---------\  |      |
 Northwestern University      | Yo      |  (o)(o) |
 Electrical Engineering       |  Dudes! \  ( <    )
 Class of 1991                \__________\ |___/  |
                                             \    |
  "Life sucks, but Death swallows!"          /    \
                                            /______\
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