Thursday, 11 February 2010

UICC and USIM in 3GPP Release 8 and Release 9

In good old days of GSM, SIM was physical card with GSM "application" (GSM 11.11)

In the brave new world of 3G+, UICC is the physical card with basic logical functionality (based on 3GPP TS 31.101) and USIM is 3G application on a UICC (3GPP TS 31.102). The UICC can contain multiple applications like the SIM (for GSM), USIM and ISIM (for IMS). There is an interesting Telenor presentation on current and future of UICC which may be worth the read. See references below.

UICC was originally known as "UMTS IC card". The incorporation of the ETSI UMTS activities into the more global perspective of 3GPP required a change of this name. As a result this was changed to "Universal Integrated Circuit Card". Similarly USIM (UMTS Subscriber Identity Module) changed to Universal Subscriber Identity Module.

The following is from the 3G Americas Whitepaper on Mobile Broadband:

UICC (3GPP TS 31.101) remains the trusted operator anchor in the user domain for LTE/SAE, leading to evolved applications and security on the UICC. With the completion of Rel-8 features, the UICC now plays significant roles within the network.

Some of the Rel-8 achievements from standards (ETSI, 3GPP) are in the following areas:

USIM (TS 31.102)
With Rel-8, all USIM features have been updated to support LTE and new features to better support non-3GPP access systems, mobility management, and emergency situations have been adopted.

The USIM is mandatory for the authentication and secure access to EPC even for non-3GPP access systems. 3GPP has approved some important features in the USIM to enable efficient network selection mechanisms. With the addition of CDMA2000 and HRPD access technologies into the PLMN, the USIM PLMN lists now enable roaming selection among CDMA, UMTS, and LTE access systems.

Taking advantage of its high security, USIM now stores mobility management parameters for SAE/LTE. Critical information like location information or EPS security context is to be stored in USIM rather than the device.

USIM in LTE networks is not just a matter of digital security but also physical safety. The USIM now stores the ICE (In Case of Emergency) user information, which is now standardized. This feature allows first responders (police, firefighters, and emergency medical staff) to retrieve medical information such as blood type, allergies, and emergency contacts, even if the subscriber lies unconscious.

3GPP has also approved the storage of the eCall parameters in USIM. When activated, the eCall system establishes a voice connection with the emergency services and sends critical data including time, location, and vehicle identification, to speed up response times by emergency services. ECalls can be generated manually by vehicle occupants or automatically by in-vehicle sensors.

New toolkit features have been added in Rel-8 for the support of NFC, M2M, OMA-DS, DM and to enhance coverage information.

The contactless interface has now been completely integrated with the UICC to enable NFC use cases where UICC applications proactively trigger contactless interfaces.

Toolkit features have been updated for terminals with limited capabilities (e.g. datacard or M2M wireless modules). These features will be notably beneficial in the M2M market where terminals often lack a screen or a keyboard.

UICC applications will now be able to trigger OMA-DM and DS sessions to enable easier device support and data synchronization operations, as well as interact in DVB networks.

Toolkit features have been enriched to help operators in their network deployments, particularly with LTE. A toolkit event has been added to inform a UICC application of a network rejection, such as a registration attempt failure. This feature will provide important information to operators about network coverage. Additionally, a UICC proactive command now allows the reporting of the signal strength measurement from an LTE base station.

Rel-8 defined a multimedia phone book (3GPP TS 31.220) for the USIM based on OMA-DS and its corresponding JavaCard API (3GPP TS 31.221).

With IP sessions becoming prominent, an additional capability to multiplex the remote application and file management over a single CAT_TP link in a BIP session has been completed. Remote sessions to update the UICC now benefit from additional flexibility and security with the latest addition of the AES algorithm rather than a simple DES algorithm.

The security model in the UICC has been improved to allow the hosting of confidential (e.g. third party) applications. This enhancement was necessary to support new business models arising in the marketplace, with third party MVNOs, M-Payment and Mobile TV applications. These new features notably enable UICC memory rental, remote secure management of this memory and its content by the third party vendor, and support new business models supported by the Trusted Service Manager concept.

A secure channel solution has been specified that enables a trusted and secure communication between the UICC and the terminal. The secure channel is also available between two applications residing respectively on the UICC and on the terminal. The secure channel is applicable to both ISO and USB interfaces.

The role of femtocell USIM is increasing in provisioning information for Home eNodeB, the 3GPP name for femtocell. USIMs inside handsets provide a simple and automatic access to femtocells based on operator and user-controlled Closed Subscriber Group list.

Work is ongoing in 3GPP for the discovery of surrounding femtocells using toolkit commands. Contrarily to macro base stations deployed by network operators, a femtocell location is out of the control of the operator since a subscriber can purchase a Home eNodeB and plug it anywhere at any time. A solution based on USIM toolkit feature will allow the operator to identify the femtocells serving a given subscriber. Operators will be able to adapt their services based on the femtocells available.

The upcoming releases will develop and capitalize on the IP layer for UICC remote application management (RAM) over HTTP or HTTPS. The network can also send a push message to UICC to initiate a communication using TCP protocol.

Additional guidance is also expected from the future releases with regards to the M2M dedicated form factor for the UICC that is currently under discussion to accommodate environments with temperature or mechanical constraints surpassing those currently specified by the 3GPP standard.

Some work is also expected to complete the picture of a full IP UICC integrated in IP-enabled terminal with the migration of services over EEM/USB and the capability for the UICC to register on multicast based services (such as mobile TV).

Further Reading:


Anonymous said...

The article is interesting. I'm trying to get more details on how the applications on the UICC are accessed. I heard about SMS, BIP and after glancing through a few 3GPP TSs I don't have a good idea on how things are done. Would appreciate if you can describe how OTA can change the IMSI (in EF-IMSI) or high priority PLMN dearch period (in EF-HPPLMN)using SMS and BIP, how will the SMS message payload or BIP look like.

Anonymous said...

Why do we have different categories for UICC / USIM in LTE? I heard about category 2 and category 2... what is the difference and can we change the categories in the SIM or we need to use a brand new SIM to change and select different category?

Anonymous said...

Can a UICC contain more than one ISIM. If yes, who assigns these multiple ISIMs and can these multiple ISIMs register separately at the same time. Is there any doc (3gpp and others) that specifically mention about multiple ISIMs in a UICC?