Abstract: A desktop cellular phone includes a SIM card with security features. To increase the difficulty of SIM PIN cracking, a SIM PIN is generated, then is encrypted by an encryption algorithm and stored in the SIM card's nonvolatile, or flash, memory. The phone's provider or carrier may use its own software program, or another suitable program, in the phone to decrypt the SIM PIN and to gain access to the features and information stored in the SIM card. As a result of the SIM PIN being encrypted, even if an unscrupulous user is able to identify the SIM PIN position in the SIM card's flash memory, it is very difficult for the unscrupulous user to obtain the PIN itself.

Abstract: A method is provided for fixing the use of a wireless communication device in certain cell areas. The method comprises: determining the predetermined number of strongest cells and checking each of the cells in descending order of received signal level to determine whether this cell belongs to one of the operator-permitted cells. If not, the signal strength of this cell is set to zero. The checking process continues until an operator-permitted cell is found, at which point the wireless terminal marks this cell as the serving cell. If after the completion of the checking of all of the cells without finding a suitable cell, the wireless terminal enters a limited service state.