[TUHS] Serial communications (was Control-T (was top))

[norman@oclsc.org (Norman Wilson)]

Clem Cole:

  WE212 modems worked on dz11 for input but just barely and could not use
  a WE dialer for output (who's number I now forget). Remember the AT
  command dialer stuff was not originally a standard from the telcos.
  The modems were independent of the dialer (which used the RS-4xx
  standard and I also have some where and I forget the number).

=====

There was certainly some WECo modems-in-a-rack-with-one-dialer setup
that could be driven by DZ11s.  I know that because that is what the
UUCP node `research' used in the 1980s, when I was at Bell Labs.

I don't know what the modem hardware was; maybe it was newer than
what Clem describes, or maybe someone (likely Bill Marshall or Joe
Condon) made some special hardware to make it work.  But the UNIX
side of things was a VAX-11/750 running Research UNIX with a DZ11;
I'm quite sure of that.

I'm also sure that the modems were genuine WECo and spoke the 212
protocol, max speed 1200bps.

Aside: when I arrived at the Labs, the standard in the Computing
Science Center was that everyone got a Jerq terminal (AT&T 5620,
commercial descendant of the Blit) at work and at home.  For the
home end everyone got a modem with attached telephone (that's the
way the official Bell stuff came back then) and a second phone
line paid for by the Labs.  There was a pool of modems dedicated
to dialin for people working from home.

A few months later, it was discovered that a Japanese modem
manufacturer (Fujitsu? I forget) had a 9600bps modem that required
a four-wire leased line but had a reasonable cost, and that New
Jersey Bell had a new offering for leased lines at a reasonable
cost too.  So the Labs paid for a pair of the modems and a leased
line for each of us, and we all brought the old 212 modems back
in when convenient, and most of the second phone lines were
cancelled.  (A few people wanted to keep them, because they were
business lines from which one could make calls to BTL offices etc
without having to submit your home phone bills for reimbursement.)

The modems had LCD status displays.  In the early samples we had
for initial testing, I vaguely remember a few spelling errors in
the status messages; in particular SIGNAL QUARITY IS POOR.  The
error had been fixed in the big bulk order.

There was one more step in the evolution of RS-232-to-home: several
years later New Jersey Bell began offering a new service called
Co-LAN to those served by certain central offices (including me).
The customer was given a box with input phone jack, output phone
jack, and a DB25 connector.  The latter afforded a serial connection
to the CO, multiplexed with the POTS signal (presumably a forerunner
of what is now called DSL).  At the CO, the serial line was plugged
into a Datakit switch.  So I would turn on my terminal and get a
Datakit prompt, type a network address referring to a system on
our Datakit network at MH, type a network-access password, and
I was connected the same as if I were at work, at 9600 bps.

New Jersey Bell hoped to sell both the service and Datakit to
other corporations; hence the password, so customers could get
only to the networks for which they were authorized.  I don't
know whether that happened much.  It was sure convenient for
Bell Labs, though.

Norman Wilson
Toronto ON