ibmpcat

I think the PC AT display is a CGA or EGA but don't know how to tell from the photo. There's what looks like a modem to the right of the display.

Your ideas and corrections are welcomed. Please add tags if there is something in the photo that a user (or search engine) might be seeking.

These are DOS machines with 5¼-inch floppy drives. The one in the foreground is some kind of IBM PC/AT and probably employs an Intel 80286 CPU. The screen might be a CGA screen. The displayed stuff looks white (phosphor) to me. I think it's a WordPerfect screen. Does this screen look like XY Write or Microsoft Word? There's a glare shield over the cathode ray tube face. There's a glare from something in spite of the attenuator.

The person in the background is using what looks like an AT&T personal computer, manufactured by Olivetti.

Networks were sometimes proprietary. I worked with 2.5 megabits per second Arcnet about this time. Newer installations had 10Base2 10 megabits per second ethernet. Both of these ran over 50-ohm chnaracteristic impeadance coaxial cable.