From The iPhone Wiki
Jump to: navigation, search

is this info correct because the the firmware showed that it is capable of a 8-16 digit and The lock on the baseband is known as a PN(Network Personalization) lock. That requires the first 6 digits MCCMNC of the stored IMSI to match the first 6 digits of the IMSI from the SIM card. The command to remove this lock is known 'AT+CLCK="PN",0,"XXXXXXXX"'. Those X's are known as the NCK, the network control key. and The firmware actually requests the IMSI three times from the SIM card. The PN check is done in the first two, while the network registration is done with the third. --liamchat 22:14, 27 September 2010 (UTC)

The NCK composition

MuscleNerd has said that he discovered the way the NCK is made. There are 15 digits, 5 for the NORID, 5 for the CHIPID and the last 5 are for the NCK key that Apple holds. Is that right? --XiiiX 16:11, 14 August 2011 (MDT)