[ih] uucp, was Question re rate of growth of the Arpanet

Clem Cole clemc at ccc.com
Tue Apr 22 12:32:11 PDT 2025


As is often the case with these sorts of remembrances, a few things are
being mixed up, and I'll try to separate them a bit: UUCP itself and the
Telebit Trailblazer, Rich Adam's work, *etc.*  As an Arpanet IP Developer
at CMU and Tektronix for the original TCP/IP VMS in 1979 and the original
mumble{}!ccc!clemc (that got grandfathered in as clemc at ccc.com when the
names space were brought together in 1982),  I'm also a past president of
USENIX as well as BOD member during some of the issues being discussed —
basically, I lived all this.

I only hope my dyslexia keeps my prose readable... so be with me and ask
questions and my apologies for my poor typing.

First, UUCP itself.  As other have said, to use UUCP it did not take much
and in the beginning, a serial port such as a DC, DL, DZ, DH, and Western
Electrical compatible automatic call unit such as a DEC DN11 (or Steve
Bellovin’s non-standard relay hack across TIP and RING noted although don’t
let the local Telco know you did that —I can explain if need be), and a
WE212 or Vadic Triple modem) whose model number I have long forgotten.  We
typically ran on Able DMAX (DH/DM) controllers because DZ's killed Vaxen
with interrupt loads and could not do hardware flow control.    A couple of
big sites UUCP “forwarding” sites were bank rolling the core of the
transcontinental UUCP circuits, inhp4 (AT&T) and decvax (Digital) that
would actually dial out to other sites with a couple of more sites in AT&T
sites in NJ, plus some slightly smaller sites like teklabs (Tektronix),
ncar (US Gov)  as well as many well know Arpanet sites the allowed dial-in
the most famous being ucbvax
[note, I'm not trying to slight anyone here, just trying to give a taste of
the many sites].

There is an essential piece of economics that feeds this monster.  First,
some wizards at AT&T realized that for every long-distance call that
ihnp4 placed,
it generated at least 12 downstream (paid) long-distance calls on the AT&T
network.  And the team in that own decvax, the Telephone Industry Group
(TIG), discovered that phone charges were not broken out.  Each group was
“taxed” for its share of the building's overhead, including heat, phones,
*etc*.  Bill Munson, TIG’s manager, once realized the cost was around $0.6
M a year, but AT&T was DEC's largest customer by far, and he rationalized
it as a cost of doing business to keep his customer happy.

That said, we all knew it would not work in the long run, hence Rich Adams —
 more in a minute.

In the early to mid-1980s, the first Telebit Trailblazer appeared,
featuring, I believe, a higher-end Z80 as its processor.  The key was that
it was sending multiple bits over the POTS audio link, thus it could
increase the data bandwidth from what the original Western Electric 212
could do, *i.e.*, obtain 56kb BW over a standard POTS line, but needed to
send additional error correction, thus it needed to buffer the data stream.
[This is why the Able boards quickly became the primary UUCP serial
interface hardware because RTS/CTS flow control was done at the UART level,
plus as a, DH11 emulation, everything as DMAs into/out of memory].

The late Greg Chesson developed the 'g' protocol for Datakit, which was the
primary protocol used by "the "Unix to Unix Copy In Copy Out — uucico"
program. Since UUCP had error correction in it, there was a bit waste,
so the Telebit
folks would put the 'g' protocol into its ROMs and could ‘fake-out’ uucico
on each.  It was all very slick.

Before I get to Rick, I need to point out what was really putting the
pressure on the USENET community — what many of us at the time called it:
net.noise but was formally called NetNews. [This author always felt that
the signal to ratio went away before 1988, but I digress].  NetNews drove
the need for the Telebit product.  We do not have the web yet, and I’m even
sure Archie or many of ‘search’ and 'indexing' function have started up.
What we have is a broadcast media, plus email.  But is the media of the
expanding news groups that is growing at a prodigious rate.
We all knew the gravy train of  ihnp4 and decvax would eventually end, just
as folks on the Arpanet were starting to see that their world would
soon change.
 The USENIX BOD considered and funded two solutions:
    • broadcasting netnews over cable (really)
    • UUNET

The first one was tried, actually ran, and was actively used for a couple
of years.  It was based on the "empty space" in the vertical sync signal of
one of the national PBS channels, with the injection point in LA.  The
advantage was that it was free for the consumers.   The original decode was
an electronics Frankenstein, which I think is what doomed this scheme.  I
made a decoder board, one as did a few others.   The plan was to get
Heathkit to offer it, but It was prototyped right around the time Heath
died. Today, we would open-source the board and the design, and I think
that might have worked.  I suspect that it failed due to the timing.

On the other hand, Rich Adam came to the USENIX board with a different
proposal.  We backed the purchase of some hardware and cosigned some
agreements so he could set up a connection to Telenet Service for incoming
connections to his new system across the USA.  His clients (like me) could
call a local number to us with a trailblazer and attach using Telenet to
Rick’s system at a very fixed cost.  This drastically reduced costs and
removed the need for ihnp4 or decvax sort the x!y!z!mysite style
addresses.  Anyone could become …!uunet!mysite inexpensively.


Clem


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