Method and device for customer personalization of GSM chips

A method for personalizing GSM chips, wherein at the manufacturer for pre-personalizing the chip a subscriber identification number (IMSI), a card number (ICCID) and an additional secret key Ki comprising the steps of:

• a) performing the personalization of the chip when the subscriber logs on to the subscriber network for the first time;
• b) obtaining the (ICCID) card number and the (IMSI) subscriber identification number from a number pool, the chip itself derives an initial secret key Ki—1 from the secret key Ki which is known and entered into the chip, while PIN and PUK are set to a default value;
• c) making an entry in an authentication center (AC) and a home location register (HLR) as soon as the subscriber has entered into a contract with a network operator;
• d) deriving at the authentication center (AC) the initial secret key Ki—1;
• e) setting the conditions of the network so that during logon to the network, a connection is established from the chip to the security center (SC) of the network operator;
• f) routing the connection from the chip to the security center (SC) during the first logon;
• g) negotiating between the chip and the security center (SC) a new second secret key Ki—2 for the chip;
• h) unconditionally disabling the conditions of step e).