9020D (as opposed to 9020E used over here as I/O processor (sort of)) sold in UK was an IBM private sale to NATS. As was HOST, the "off the shelf" "interim" replacement for the 9020 pending Advanced Automation System.
Running a replacement to the Host hardware/OS (sort of) now and looking for a further replacement under ERAM (Enroute Automation Modernization).
Several things jump out:
1. Yanks think up neat names for stuff
2. Brits are smarter because they let us develop the stupid things and then come in and say "one more here please" and just pay the recurring cost.
3. NAS is old
Can you guys develop a replacement for NAS and then the FAA just buy it for the recurring cost? Please?