Thank you trewmte, I apologize for not being more precise.
Lets make some assumptions: The mobile is fully functional and the Universal Integrated Circuit Card UICC (aka SIM card) not damaged. No hardware failure nor software bugs. Lets find out what states a UICC can have, I propose:
- non activated
- activated (valid)
- temporary blocked
- blocked
- disactivated
It differs from country to country if a UICC already has a 'phone number' assigned (MSISDN). Some operators pre-assign (e.g. Switzerland, users can choose a 'phone number'), some operators assign after registration process, authentication with ID or passport.
So who triggers messages - based on above assumptions? Which messages always come from the device, which messages always come from the network side (operator)?
One sample I have: SIM registration failed. As a mobile registers at a network this for sure comes from the network side. Normally no messages come to the user as registration is a background process.
Have to add that there are two types of messages: On-screen and top bar (where you usally see 2G, 3G, H+, HSPA, CDMA, 4G, LTE and so on) close to signal strength indicator bars.
Maybe its good to learn which messages come from whom...
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