Universal integrated circuit card

The UICC ensures the integrity and security of all kinds of personal data, and it typically holds a few hundred kilobytes.

1 and NIST Computer Security Resource Center Glossary state that, "A UICC may be referred to as a SIM, USIM, RUIM or CSIM, and is used interchangeably with those terms",[3][4] though this is an over-simplification.

[citation needed] A UICC consists of a CPU, ROM, RAM, EEPROM and I/O circuits.

Thus, the R-UIM card can be inserted into CDMA, GSM, or UMTS handsets, and will work in all three cases.

Since the card slot is standardized, a subscriber can easily move their wireless account and phone number from one handset to another.

Another code, PIN2, can be set, to allow the use of special functions (like limiting outbound telephone calls to a list of numbers).