> [TELECOM Digest Editor's Note: One of the larger private systems was
> 'Unitel' which was the United Airlines private network. I recall
> when we discovered a seven digit local number in Elk Grove, IL termin-
> ated on tne Unitel network and the type of things which could be done
> on that network. ...
> Both Unitel and Stanotel were very unusual hybrid systems, and I
> expect, quite expensive to maintain, but apparently _less expensive_
> than toll charges had the Bell System been used. PAT]
Were the above networks truly "private", that is, owned, maintained,
and operated by the corporations? Since you could dial into them from
the outside, it sounds like they were Bell provided "SCAN" networks.
I forgot what SCAN stands for, but many very large corporations had
(have) them to interconnect different locations. It was basically a
sophisticated network of WATS, tie-lines, and FX lines*. A telephone
would have two numbers on the number card, one the regular Bell number
and one the SCAN number. To use SCAN, users typically dialed 8 (or
another access code), then the SCAN number. On some systems, you
could get an outside line in a distant city to avoid toll charges.
They are still in use today.
The outside access was to allow employees, such as salesman, to call
in and connect anywhere without toll charges.
Years ago employees of such companies would love such systems because
it enabled them to call friends/relatives in distant cities without
toll charges. The corporation might not be paying for an individual
call, but it did have to pay for the tie-lines and heavy personal use
meant it had to add more very expensive WATS or tie- or FX lines.
* A tie-line is a trunk that interconnects two separate PBX systems.
A "FX" foreign exchange is a telephone line that is served by a
distant city. This enables callers to reach a company via a local
call and a company to call that distant place without toll charges.
An example of use is major resorts having reservation lines to big
cities. For example, Catskill resorts would have tie lines to New
York City, Pocono resorts would have tie lines to Philadelphia. On
the switchboard tie lines had special heavy wire since they had higher
line voltage to accomodate the distance.
Also, many suburban businesses and residences had FX to a city
exchange to avoid paying message unit charges in both directions. For
businesses this is a consideration.
[TELECOM Digest Editor's Note: Although Stanotel was always closely
guarded against outside intrusion, the only reason Unitel was wide
open was due to stupidity; the manager of same did not know how to
block any sort of intrusion. One of the first things I did after
learning about Unitel was verify the local Elk Grove numbers. Using
the old, stale trick of dialing a 'local' (9-level) call as a zero
plus call to the Waldorf-Astoria hotel in New York City person to
person to Mr. Smith, I asked my operator to leave word if Mr. Smith
had not yet checked in. "Surely," she responded, and told the Waldorf-
Astoria operator to leave word for Mr. Smith, asking 'him' to call
Operator 7 in Chicago and that the number calling was (whatever). Had
I simply dialed the operator and asked what my number was, I would
have been told I should know my own number, and refused any further
information. _Thank you_, operator. Two or three months later, I
discovered the inbound number for Unitel was no longer getting
answered, so on a hunch I dialed the formerly _outbound_ number, and
as I suspected, it was answered by dial tone. The only thing the
foolish people had done was swap the two numbers in the plug-in
call-extender device. That was _their_ notion of what security was
all about (this was the 1980's). So, Lisa, strictly speaking, Unitel
nor Stanotel were intended for 'public' use.
A third example of this was Chicago, Nilwaukee and Northwestern
Railroad which had a large office in Chicago, wherein they had a
Dimension PBX. No one from telco ever bothered to explain to any
railroad employees that Dimension always had a remote port on it
for 'testing and repair' purposes, with its own distinct phone number
on that line. Nor did they ever explain that the passcode on such
systems was factory-defaulted to four zeros, i.e. '0000'. The rail-
road found out the hard way on that; a phone bill one month in the
thousands of dollars. The last thing I heard (late 1970's) two
Illinois Bell Security guys were roaming around up in Minnesota trying
to track down recipients of phone calls. PAT]