Path: utzoo!utgpu!watserv1!watmath!att!tut.cis.ohio-state.edu!snorkelwacker!apple!sun-barr!newstop!sun!coherent!dplatt
From: dplatt@coherent.com (Dave Platt)
Newsgroups: comp.dcom.modems
Subject: Re: Error-correcting modems & uucp
Message-ID: <52776@coherent.coherent.com>
Date: 13 Apr 90 04:24:05 GMT
References: <963@frcs.UUCP> <967@frcs.UUCP> <1147@chinacat.Unicom.COM> <1990Apr12.002225.7496@imax.uucp>
Reply-To: dplatt@coherent.com (Dave Platt)
Organization: Coherent Thought Inc., Palo Alto CA
Lines: 26

In article <1990Apr12.002225.7496@imax.uucp> dave@imax.com (Dave Martindale) writes:
> A possible exception to this is if you have non-PEP uucp connections.
> For those, no spoofing will be done, and you may have to turn off flow
> control.  (or maybe not - uucico will only send 3 64-byte packets
> before waiting for an acknowledgement; the modem may not flow-control
> that small an amount of data).

With the TrailBlazer Plus, you must turn off flow control if you have a
non-spoofed UUCP connection and are running the modem-to-host connection
at a higher speed than the modem-to-modem connection.  The TB+ drops
CTS quite quickly (its window is less than the 3-uucp-packet high-water
mark) and ignores data which the host sends after that point.  According
to someone at Telebit with whom I spoke, the decision to drop CTS so
quickly was a deliberate one... it ensures that interactive users can
hit control-C (or whatever) and see the effect quickly when operating in
this mode.

Unfortunately, there's apparently no way to adjust the flow-control
threshold (say, raise it to 256 bytes or so);  it's either on, or off.


-- 
Dave Platt                                             VOICE: (415) 493-8805
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