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sim-card

If sim card cloned, can we use it in real world?

Is the SIM card, COMP128 v1 and another version can be cloned? In real network operator can we use it and have two SIM card?

Solution

  • The answer is Yes and No, depending what you mean by two SIM cards.

    If you have two identical SIM cards identified by their same IMSI and Ki (Key). Only one will work at any time.

    If you use SIM1 in a device it will authenticate to the network and receive what is called a TMSI (Temporary Mobile Subscriber Identity). The network will from now on address this subscriber by this TMSI.

    If you start up SIM2 the authentication will happen and the network will associate you with a new TMSI.

    Any SMS or Call will re routed to the last "authenticated" SIM. authentication could be retrigged by bootup, location change etc.