4 Overview of USAT

31.1113GPPRelease 18TSUniversal Subscriber Identity Module (USIM) Application Toolkit (USAT)

The USAT provides mechanisms which allow applications, existing in the UICC, to interact and operate with any ME which supports the specific mechanism(s) required by the application.

The following mechanisms have been defined. These mechanisms are dependent upon the commands and protocols relevant to USAT in TS 31.101 [13].

4.1 Profile Download

Profile downloading provides a mechanism for the ME to tell the UICC what it is capable of.

4.2 Proactive UICC

Proactive UICC gives a mechanism whereby the UICC can initiate actions to be taken by the ME. The supported functions are specified in clause 6.4.

For each command involved in the dialog with the user, a help information may be available, either for each item of a list of items proposed to the user, or with each command requesting a response from the user. If a proactive command involved in the dialog with the user indicates the availability of the help feature, the support of this feature is optional for the terminal.

4.3 Data download to UICC

Data downloading to the UICC uses either dedicated commands (the transport mechanisms of SMS point-to-point and Cell Broadcast) or the Bearer independent protocol. Transferral of information over the UICC-ME interface uses the ENVELOPE command.

4.4 Menu selection

See ETSI TS 102 223 [32] clause 4.4.

4.5 Call control by USIM

When this service is activated by the USIM, all dialled digit strings, supplementary service control strings and USSD strings, PDP context parameters, PDN connection parameters, PDU session establishment parameters or IMS communications parameters are first passed to a USIM application before the ME sets up the call, the supplementary service operation or the USSD operation, establishes the PDP context, the PDN connection, the PDU session or initiates IMS communications. The ME shall also pass to the USIM application at the same time its current serving cell. The USIM application has the ability to allow, bar or modify the call, the supplementary service operation or, the USSD operation, PDP context activation, PDN connection activation, PDU session establishment or IMS communication set up by another context activation. The USIM application also has the ability to replace a call request, a supplementary service operation or a USSD operation by another call request or supplementary service operation or USSD operation.

EXAMPLE: A call request can be replaced by a supplementary service operation or a USSD operation, and vice-versa.

4.6 MO Short Message control by USIM

When this service is activated by the USIM, all MO short messages are first passed to the USIM application before the ME sends the short message. The ME shall also pass to the USIM application at the same time its current serving cell. The USIM application shall have the ability to allow the sending, bar the sending or modify the destination address of the short message before sending it.

4.7 Event download

In addition to the set of events defined in ETSI TS 102 223 [32] clause 4.7, the following event may also be reported to the UICC:

– Network Rejection

– CSG cell selection (if class "q" is supported)

– Incoming IMS Data (if classes "e" and "t" are supported)

– IMS Registration (if classes "e" and "t" are supported)

– Data Connection Status Change (if class "e" is supported)

– CAG cell selection (if class "ag" is supported)

– Slices Status Change (if class "ah" is supported)

4.8 Security

See ETSI TS 102 223 [32] clause 4.8.

4.9 Multiple card

See ETSI TS 102 223 [32] clause 4.9.

4.10 Timer Expiration

See ETSI TS 102 223 [32] clause 4.10.

4.11 Bearer Independent Protocol

See ETSI TS 102 223 [32] clause 4.11.

4.12 Description of the access technology indicator mechanism

See ETSI TS 102 223 [32] clause 4.12.

4.13 Description of the network search mode mechanism

See ETSI TS 102 223 [32] clause 4.14.

4.14 Geographical location discovery

The proactive command Geographical Location Request and the envelope command Geographical Location Reporting allows the UICC to request and receive the current geographical location information from the ME when the ME is equipped with a positioning feature and it is enabled (e.g. autonomous GPS, Assisted GPS or Assisted GNSS).

4.15 Operation in reduced USAT capable terminals

This specification takes into account terminal types corresponding to the following capabilities:

– no display capability

– no keypad available

– no audio alerting capability

– no speech call capability

– no support of multiple languages.

These terminal types are used to identify which USAT features are not available for each type of reduced functionality.

Note: Terminal types details are in Annex P.

4.16 Tag allocation guidelines

See ETSI TS 102 223 [32] clause 4.13.

4.17 USAT over the AT interface

See ETSI TS 102 223 [32] clause 4.16.

4.18 USAT facilities provided by eCAT clients

Not required by 3GPP.

4.19 Negotiation of Poll Interval

See ETSI TS 102 223 [32] clause 4.18.

4.20 ProSe usage information reporting

When the UICC supports the ProSe usage information reporting functionality, the ProSe-enabled Public Safety UE stores in the UICC the information to provide information necessary for composing of charging events related to the ProSe direct communication. The UICC is responsible for communicating those reports to the ProSe Function CTF (ADF) using BIP mechanism.