Point of correction, you IMEI doesnt ping anything of the sort this is your IMSI two distinct and different things, one is attached to your mobile device the other on your SIM card , for a telco to locate you , it uses a different method eg SS7 , HLR(home location reg) and VLR https://twitter.com/theo_mwangi/status/1280517642831478798

The GSM stack and the VPN stack are two different technologies not relying on each other in any way , a VPN is on the IP stack layer under network , application , local access while GSM is not on this stack spectra , not to say it doesn’t employ some of the capabilities

Also IMEIs are unique but they are not conditioned not to allow multiple devices with same/cloned IMEI , an IMEI only identifies the product , this is used when tracking phones as that’s the identity of the phone ... when tracking a person , both IMEI and IMSI come to play

IMEI (international mobile equipment identity/identifier) 15digit unique identifier for mobile termainals (phone, modem, POS etc) IMSI (international mobile subscriber identity/identifier) 15 digit code , containing MCC and MMC (mobile country code and mobile network code)

MCC each country has an MCC kenya is 639
MNC each operator has an MNC allocated too safaricom 02, airtel 03 , Yu was 05 and Telekom 07

So your IMSI might look like 639-02/03/05/07(then 10 digits)

Now let’s get to the most simple way on how your phone communicates:

First your phone , is a screamer for attention ... starts soon as you boot it up, first thing it will do on network , is offer a challenge to the provider (this challenge is used to authenticate)

Sort of like a password you know , but this is done using a challenge response mechanism where your phone sends out a random key and the mobile service provider generates an SRES response , this using an subscribers Ki (pronounced key) giving you a session (Kc) in all this ...

Your phone gets a unique TMSI (temporary IMSI) useful does that your IMSI doesn’t leak (why you ask?) security purposes ,

Let’s side step to explain how phones are tracked(local tracking) not remove over a long range eg 30km and above

Another thread ..