3 Jul
2015
3 Jul
'15
10:48 a.m.
I was going to write almost exactly this ... although the Wiki page
mentions that AT&T was one of the primary customers of the System/7, AFAIK,
the common control on the 1/2/3/4ESS switches was a proprietary WECo design
that was highly integrated into the design of the switch itself ... in the
5E, I think the common control became a 3B20D mini and later this was
replaced with an emulator of same running on some number of SPARCstations
...?
For operations support systems, I thought DEC was very popular in the Bell
System; I thought many OSS ran on some modified UNIX variant or another on
PDP-11 or, perhaps later, VAX which would have roughly been contemporaneous
with the System/7 ... I would be really interested to know what the
System/7 did at AT&T if anyone is familiar.
I have a particular interested in collecting digital telephone switches ...
and I too find it a real bummer that we could find ourselves in a world
where there isn't one complete, functional example of such historic
machines as the 1AESS, 4ESS, DMS-100, 5ESS and so on. Many completely
functional examples of the old cord-boards and even the electromechanical
step-by-step and crossbar switches exist in private hands but as far as I
know, nobody has managed to save a complete digital CO switch of any
vintage.
Best,
Sean
On Thu, Jul 2, 2015 at 11:33 PM, Christian Gauger-Cosgrove <
captainkirk359 at gmail.com> wrote:
On 2 July 2015 at 17:39, Mike Ross <tmfdmike at
gmail.com> wrote:
Take the IBM System/7. Successor to the 1800,
succeeded by the
Series/1. They were *ubiquitous* - one in every telephone exchange in
the USA, I've heard. They even made a special ruggedised version for
Being
into telephony, I can say that I've not heard anything about IBM
System/7 machines being used in exchanges. I do know that the WECo ESS
exchanges did, of course, have computers. But the ESS exchange
computers were custom systems and architectures built by Western
Electric.
The 1ESS/1AESS computer architecture is however, nearly completely
extinct. There are, I believe, only two 1ESS/1AESS switches left. One
is a partial, and non-functional exchange at the museum of
communications in Seattle; the processor is complete, and it has one
of each requisite switching frame, but it can't be used as they need
to recompile the software that runs it (which isn't possible as
they're lacking the crucial internal compiler that ran on WECo's IBM
System/3x0 machines). The other 1ESS/1AESS switch is a complete and
functional unit, still in service, last I heard. But there are plans
to scrap it and put in a modern switch in its place. Saving it would
be a difficult proposition, to say the least.
Regards,
Christian
--
Christian M. Gauger-Cosgrove
STCKON08DS0
Contact information available upon request.