Phil Karn says:
Interesting. As expected, when I called 1-800-235-1414 from a PBX extension here at work, it read back the trunk number, not my actual extension number. The same for a developmental CDMA digital cellphone, since we use PBX-style trunks from our switch.
But when I called it from a conventional AMPS (FM) cell phone using Pac Tel Cellular, I also got a number that was different than my mobile's real number. And when I called it back, I got a number-not-valid intercept.
Interesting. Apparently one real cellular switch also looks like a PBX as far as ANI goes. I wonder how widespread this is. Anybody with a cell phone on a service other than Pac Bell who is willing to give it a try?
I have an even stranger datum to report -- when called from the ISDN PBX here, ANI gets not just the building trunks but *MY* phone number. Yes, it got the extension right, on the other side of the PBX. Hmmm... .pm