Chapter 1: Product Features
June 30, 2008 AT Commands Reference Manual 1-3
Service Provider (ISP) to send email or dialing the corporate Intranet to set up a virtual private
network (VPN) connection to retrieve confidential customer information from a company
database.
Improved OEM Features
G24 contains the following new and improved features:
SIM Application Toolkit (STK)
TCP/IP support
Audio (digital and analog) - path, gain and algorithm
User-defined profiles
For a full list of G24 features, refer to the G24 Module Hardware Description manual.

SIM Application Toolkit (STK)

Overview
The SIM Toolkit (STK, also known as the SIM Application Toolkit or SAT) is a set of
applications operated by the network provider (usually the module's SIM provider). If the STK is
supported and enabled on the mobile side, specific data can be obtained via menu browsing.
Features and Benefits
The G24 STK enables the terminal to obtain information via menus created by the provider, for
example, "local news" or "weather info". These menus are provider dependent. Enabling the STK
allows the provider to perform other actions regarding call control, SMS etc.
Technical Description
The STK supports the specific mechanism(s) that SIM applications require to interact and operate
with the G24. Using this mechanism, the SIM can notify the terminal, via the G24, that a specific
action is requested. A full list of supported actions is listed in the Proactive SIM section. For more
information regarding the STK mechanism, refer to the GSM 11.11 [20], GSM 11.14 ETSI
standards.

Profile Download

Profile downloading provides a mechanism for the G24 to transmit information describing its
capabilities to the SIM. During the early, profile download phase of the protocol, the G24
negotiates and confirms its ability to support the capabilities requested by the STK.

Data Transfer into the SIM

STK data transfer uses the short message service (SMS) as a transfer layer.