Chapter 14 – SIM Toolkit
Multi-Tech Systems, Inc. Wireless GSM/GPRS AT Commands (Document Number S000293I) 138
Overview of SIM Application Toolkit
SIM Toolkit, also known as “SIM Application Toolkit,” introduces new functionalities which open the way to a broad range of
value added services. The principle is to allow service providers to develop new applications (e.g.. for banking, travel, ticket
booking, etc.) for subscribers and to download them into the SIM.
This solution allows new services to be accessible to the user by adding new SIM-based applications without modifying the
handset.
Functionality
The term SIM Toolkit refers to the functionalities described in the GSM Technical Specification 11.14. It introduces about
twenty-five new commands for the SIM. Three classes of Toolkt functionalities have been defined, with Class 1 offering a
subset of commands and Class 3 offering the full range of commands (See the Support of SIM Toolkit Classes table in
APPENDIX D).
The SIM Application Toolkt supports:
• profile download
• proactive SIM
• data download into SIM
• menu selection
• call control by SIM
Profile Download
The Profile Download instruction is sent by the customer application to the SIM as part of the initialization. It is used to
indicate which SIM Application Toolkit features the customer application supports. The AT command used for this
operation is +STSF (SIM Toolkit Set Facilities).
Proactive SIM
A proactive SIM provides a mechanism whereby the SIM can ask the customer application to perform certain actions.
These actions include:
• display menu
• display given text
• get user input
• send a short message
• play the requested tone
• set up a call
• provide location information
This mechanism allows SIM applications to generate powerful menu-driven sequences on the customer application and to
use services available in the network.
The commands used for this operation are:
+STIN (SIM Toolkit Indication),
+STGI (SIM Toolkit Get Information),
+STGR (SIM Toolkit Give Response).
Data Download to SIM
Data downloading to the SIM allows (SMS, phonebook…) data or programs (Java applets) received by SMS or by Cell
Broadcast to be transferred directly to the SIM Application.
This feature does not need any AT command. It is transparent to the customer application.
Menu Selection
A set of menu items is supplied by the SIM Application Toolkit. The menu selection command can then be used to inform
the SIM Application which menu item is selected.
The commands used for this operation are +STIN, +STGI and +STGR.
Call Control by SIM
The call control mechanism allows the SIM to check all dialed numbers, supplementary service control strings and USSD
strings before connecting to the network. This gives the SIM the ability to allow, bar or modify the string before the
operation starts.
The commands used for this operation are:
+STCR (SIM Toolkit Control Response)
+STGR (SIM Toolkit Give Response)