It’s great if you want to set up a few base stations at Burning Man and hand out SIM cards like ecstasy, but GSM has encryption. You won’t be able to decrypt every GSM signal this system can ...

This is a fully-functional SIM for public networks ... Everyone at Electromagnetic Field 2018 gets one of these GSM phone badges. Read Hackaday’s first look at the hardware.

A multi-carrier GSM phone with two, three or four SIM cards. Dual-SIM phones are popular with global travelers who use local and foreign carriers as well as people who want a business and personal ...

(Subscriber Identity Module lock) A function in GSM cellphones that restricts the phone's use to a particular cellular carrier identified by a SIM card. SIM locks are used to ensure subscribers ...

GSM phones can be "locked", that is made to accept only SIM cards belonging to a specific network. Typically, this is done so that phones will work only on the network of the carrier. SIM-locked ...