Universal Integrated Circuit Card

The Universal Integrated Circuit Card (UICC) is the smart card used in mobile terminals in GSM and UMTS networks. The UICC ensures the integrity and security of all kinds of personal data, and it typically holds a few hundred kilobytes. With the advent of more services, the storage space will need to be larger.

In a GSM network, the UICC contains a SIM application and in a UMTS network it is the USIM application. A UICC may contain several applications, making it possible for the same smart card to give access to both GSM and UMTS networks, and also provide storage of a phone book and other applications. It is also possible to access a GSM network using a USIM application and it is possible to access UMTS networks using a SIM application with mobile terminals prepared for this. With the UMTS release 5 a new application, the IP multimedia Services Identity Module (ISIM) is required for services in the IMS. The telephone book is a separate application and not part of either subscriber identity module.

In a cdmaOne/CDMA2000 ("CDMA") network, the UICC contains a CSIM application, in addition to 3GPP USIM and SIM applications. A card with all 3 features is called a removable user identity card, or R-UIM. Thus, the R-UIM card can be inserted into CDMA, GSM, or UMTS handsets, and will work in all three cases.

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