Am 10.11.2017 um 15:24 schrieb Darac Marjal:
The easiest solution is to not fit a SIM card, however, be aware that
in some countries limited cellular access may be possible even without
a SIM card (for example, in some countries you can call emergency
services from a phone with no SIM card; in some you do need a SIM card
even if it is out-of-range, blocked or not activated).
Its in fact part of the spec.
Part of the GSM authentication and network attach spec allows any device
w/o a SIM, or without a valid SIM, to attach to the network, and will
accept emergency calls.
E.g. If you have a T-Mobile phone, and occasionally see it in SOS mode,
what's happened is that the phone can't see a T-Mobile tower, and
connects to an AT&T tower instead. There's no roaming agreement, so AT&T
won't let the device onto the network, but will accept SOS calls.
