Not to put too fine a point on it, but the packets we're exchanging over the internet don't contain the IP address either. That information is part of the IP wrapper which bloats all IP socket communications. It's there, it's available, but it's added as part of the protocol, NOT by the application developer's code EVEN is he's writing native sockets -- that is, it's not application payload, it's protocol payload. I identify the "to" ip when I open the socket, the network stack puts it in the wrapper for me. I NEVER identify the "from" ip, but the IP portion of the stack adds that too. The guy receiving the packet need not even step around the IP, because it's not "application payload", it is part of the protocol data. I am interested, though, how a system would be able to definitively marry your current position with your position moments prior without having an ID in the information (though perhaps not the "payload") communicated. You could say "trend analysis" I suppose. You know, "That guy is closest to where some other guy was a moment ago, so he must be the same guy." It might be a good enough kludge for 1950's technology, but is that really how we're going to do it in 2020? ETA: the answer to that last question is squawk code. . . it might take a little research to disprove that, it could be true. I jsut know I've seen 8 minute long flights and didn't immediatly think, "I wonder what flight following was like for that flight." You know, when you're considering buying a plane, you want to know how fast it goes. . .
I suppose I'll make this my final statement about it. Continued discussion is unfair to iFly. Go ahead everyone, flame away about how anonymous we are until we have a squawk.
Check out this dude:
https://flightaware.com/live/flight/N91407
Takes off from an uncontrolled airport, and does practice flying over the desert at 2500 AGL, never entering anyone's airspace, for 24 minutes. . . and he got a squawk code to do it. . . I guess. The Barnstormers ad says "annual just completed". The flight was at the end of March. I suspect it was a checkout flight after the annual was completed.