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From: Mills@UDEL.EDU.UUCP
Newsgroups: comp.protocols.tcp-ip
Subject: Re:  Dial-up TCP/IP (was interactive SMTP over phone lines)
Message-ID: <8705130005.a009458@Huey.UDEL.EDU>
Date: Wed, 13-May-87 00:05:47 EDT
Article-I.D.: Huey.8705130005.a009458
Posted: Wed May 13 00:05:47 1987
Date-Received: Fri, 15-May-87 07:12:23 EDT
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Vint,

I can't resist observing that, in the nine years or so I have been running
dial-up 1200-bps IP links (mostly over metropolitan areas), the incidence of
packets lost to transmission errors has been much less than those due to
the circuit simply going on-hook. The nice thing about TCP and the latter
is that you can redial during the user-timeout interval, while TCP is
retransmitting, and things just go on as before. Now consider the amateur
TCP/IP packet-radio experiments being conducted by Phill Karn and several
others (including myself), where the packet loss can be as high as one in
three on the radio channel. I would agree from experience that the channel
protocol needs to be reworked entirely before expecting TCP retransmissions
to save the day.

Obviously, Phill and friends are leapfrogging the dial-in issue. You want
ubiquitous access? Look ma, no telephones or wires even.

Dave