Re:What is AT&T doing at 1111340002?
by lxgr on Sunday November 07, 2021 @08:13AM
(#29139184)
Probably none at all – such a SIM wouldn't have the required keys to even connect to any real network.
SIM cards are just Java Cards, after all – the secret sauce is the proprietary software running on them (the ones you've linked seem to come with an implementation of that pre-loaded) and of course the keys they hold.
Nobody keeps you from implementing all the SIM specifications in an open-source Java Card application, and I would in fact be very intrigued to see it happening ;) As far as I know, experimental/hobbyist GSM networks, like the ones running at some conferences, are still using proprietary SIM cards, and an open source implementation would be very interesting to study.
SIM cards are just Java Cards, after all – the secret sauce is the proprietary software running on them (the ones you've linked seem to come with an implementation of that pre-loaded) and of course the keys they hold.
Nobody keeps you from implementing all the SIM specifications in an open-source Java Card application, and I would in fact be very intrigued to see it happening ;) As far as I know, experimental/hobbyist GSM networks, like the ones running at some conferences, are still using proprietary SIM cards, and an open source implementation would be very interesting to study.