I would like to create my own GSM network (base station with mobile devices connected to each other) and having voice/sms services. Something like demonstrated here: https://evilsocket.net/2016/03/31/how-to-build-your-own-rogue-gsm-bts-for-fun-and-profit/
I thought of creating my BTS station and device in lab without being connected to the outside world.
But If I understand correctly, on creating such BTS it will "automatically" be connected to the outer world (so that device in my own lab will see other devices), Right ?
Is it possible to create such network isolated from outer world ?