@Alonewolves .. thanks for the answer, i know that the IMSI code is unique to the Sim card, and it is hard coded inside the SIM card.
But can the IMSI be changed ? with other words it detects in wich country you are on, and then using a script the IMSI is updated “over the air”. And supposing that the updated IMSI is already valid, then you are not international roaming anymore, it is correctly understood ?
i know that you can change the IMSI using OTA programming, and maybe it can be done “over the air” .. but is the hole idea faisable, it is just i have to discuss that in my school project.