On 13 Sep 2007 at 17:36, Roy J. Tellason wrote:
And I'd
also disqualify device-sharing, such as a MAC (multiple
access controller) between an I/O device and two computers. Those go
WAY back...
I'm not familiar with such stuff.
Ah, showing my age. "Back in the day" you might have two otherwise
independent mainframes and, say, two printers. To have a system do
nothing but wait for a print job to finish while only one of the
printers was busy is a huge waste of resources. A card punch might
be an infrequenly used piece of equipment, so why have two? Or a
printer could be offline for maintenance, but why take the machine it
was attached to down also? Or, instead of having two banks of 8 tape
drives for two machines, why not whittle that down to, say 12, and
allow the drives to be shared? IIRC, most vendors offered some sort
of a MAC facility, even if it was a QSE. CDC certainly did.
Of course, direct coupling of computers was also done, either via a
special I/O device or even shared bulk core. But we never called
that "networking".
Cheers,
Chuck