Thanks for the links. There’s some new information in there that I’ll have to look further into. For one, I’ve never heard of security concerns about 5G versus 4G.
I also wasn’t aware of the TMSI at all. I still don’t fully understand some things about it which would be important considerations:
How is this randomized number assigned/correlated to the IMSI? Is it done by the tower?
It seems like the carrier can request the actual IMSI at any time. Can these CSS also do that? TMSI is supposed to protect against ‘eavesdroppers’ but these industrial a grade CSS might have greater capabilities than passive eavesdropping.
I am unsure if or how disabling roaming would protect you from CSS. For one, the spoofing might make your device think it isn’t roaming. Secondly, the CSS might still be aware of your device anyway, even if it doesn’t establish an open connection to it. The phone and the tower need some minimum communication to even determine if you’re roaming or not.