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Path: utzoo!watmath!clyde!burl!ulysses!allegra!princeton!down!honey
From: honey@down.FUN (Peter Honeyman)
Newsgroups: net.dcom
Subject: Re: modem evaluation - Telebit Trailblazer
Message-ID: <687@down.FUN>
Date: Wed, 30-Apr-86 08:16:15 EDT
Article-I.D.: down.687
Posted: Wed Apr 30 08:16:15 1986
Date-Received: Sun, 4-May-86 04:29:51 EDT
References: <1703@sdcsvax.UUCP> <137@portal.UUcp> <280@mit-vax.UUCP>
Organization: CS Dept., Princeton University
Lines: 19

rick adams and i have been experimenting with the telebit
trailblazer and uucp.  we found that piet's 'f' protocol
gives good performance.

but.

when the receiving host is loaded, dz overruns are a high
probability event.  similarly, when line noise forces modem
retransmissions (yes, it retransmits on corrupt checksum),
the sender overruns the modem.  we found this to be a critical
problem at 9600, and a moderate one at 4800.

the modem wants hardware flow control, but unix drivers tend
not to support it.  (i am told there is a vax hardware problem
here.)  i considered hacking an 'F' protocol that runs 'f' in
cbreak mode with dc1/dc3 flow control, but am unmotivated.  and
there's no guarantee that even this would suffice at 19200.

	peter