Proprietary. Union Switch & Signal ASES (Advanced Speed Enforcement System). I was Lead Software Engineer.
But still, it does puzzle me why it wasn’t doing anything now. Why it was retired so soon, or was it not retired and it just failed?
That’s a question I might ask into locally. I had assumed, wrongly, that railroads were going from being naked to the current PTC system... not from earlier PTC systems to this one. If the latter, then there would be some transition plan.
What sort of technology did the system you put in use, broadly speaking? I’m not aware of what the NJ Transit is using now but I believe Amtrak uses transponder-based tech (unlike most of the freight roads). Maybe the old system wasn’t compatible? Or just didn’t get FRA cert? I wasn’t aware that there were any FRA-approved PTC systems that long ago.