Well that's cool... industrial networking, token passing, kind of like arcnet, uses 75 ? cable.
Does this spec have a name?
Allen Bradley Vista Lan is one product ( we're talking early 1990's now ) . Arcnet itself was never part of IEEE specs, preceded the specs. It was invented by Datapoint and was very robust.
Here's a reference.
[ame="http://en.wikipedia.org/wiki/ARCNET"]ARCNET - Wikipedia, the free encyclopedia[/ame] .
I used Arcnet Plus for it's "long legs" in an installation to link ethernet subnets, before fiber was installed in our plant. The 20Mbps data rate was quite sufficent for the traffic .