|
|
31 series - USAT interpreter architecture and protocol stack
Description
The USAT interpreter encodes the commands and responses in the USAT, and transports them between the UICC and an external application system. This allows the application to send USAT commands to the UICC, and hence to mimic the behaviour of an application within the UICC itself.
As shown above, the application uses the USAT interpreter to communicate with the ME's user interface, for example by displaying menus and waiting for the user's selection. The USAT interpreter is typically used for web browsing, in a way that makes good use of the user-specific security capabilities of the UICC.
The commands and responses are typically sent by SMS, and are secured using the USAT security procedures.
Abbreviations
| ME | Mobile equipment |
| SMS | Short message service |
| UICC | Universal integrated circuit card |
| USAT | USIM application toolkit |
|