For the purposes of this TS the following definitions apply: applet: application: bearer independent protocol: buffer: content: data channel: link: USAT service: USAT execution environment: USAT serving environment: USAT subscriber: USAT server: user: (U)SIM:

For the purposes of this TS the following abbreviations apply: API CAMEL CS CSE IN ME MExE MMI NO PLMN SAT SCI SIM UE USAT USIM Further abbreviations are given in TR 21.905.

The (U)SIM-API is defined in ETSI TS 102 240 [18]. This API is valid for (U)SAT and is referred to in this TS as (U)SAT API. The (U)SAT API for the UICC shall allow application programmers easy access to the functions and data described in TS 51.011, TS 31.101, TS 31.102, TS 51.014, TS 31.111, such that (U)SIM based services can be developed and loaded onto UICCs (independent of the UICC manufacturer), quickly and, if necessary, remotely, after the card has been issued. The (U)SAT API shall support pro-active functions as described in TS 51.014 and TS 31.111, and transport functions as described in TS 51.011 and TS 31.102.

The USAT proactive capability is a mechanism whereby the UICC can request specific actions to be taken by the ME by issuing "proactive commands" thus establishing and maintaining an interactive dialogue with the user and/or communicating with the network or an external device. An ME may have a variety of configurations, for example, it may consist of a modem connected to an external display. The USAT proactive capability requirements are applicable to the ME as a whole without regard to any particular configuration. The ME shall inform the UICC of the success or otherwise of each command issued to it by the UICC, and also indicate the command details and if applicable add more specific information. The proactive command set allows the USAT to instruct the ME to:

1. display text supplied by the USAT on the ME's display, with an indication of priority (normal or high), and a defined action (user activity or timeout) to terminate the text display.
2. display a text string and obtain the response in the form of a single user keystroke or a string of keys entered by the user and pass the response to the UICC. If the response is designated as private by the UICC the ME shall not display the users response on the screen.
3. set up a voice call to an address with a specific priority as indicated by the UICC with all parameters indicated by the UICC.
4. set up a data call to an address with specific bearer capability and priority, all parameters are indicated by the UICC.
5. set up and manage a data channel (using CSD, Packet service bearer (e.g.: GPRS, UTRAN packet service, HSDPA, …), SMS, USSD or I-WLAN) between the UICC and an address using information provided by the UICC. It shall be possible for the USAT application to provide the ME with the network connectivity parameters to be used (e.g. PDP context parameters) to establish IP connectivity between a USAT application and a remote entity.
6. send data through a previously set up data channel. The UICC informs the ME if the data is to be sent immediately.
7. retrieve data from the ME that has previously been received via a data channel set up using (5) above. The UICC informs the ME as to how much data it expects to retrieve.
8. send a short message to the network. The short message text is supplied by the UICC to the ME in either packed or unpacked SMS 7-bit alphabet, or UCS2 alphabet.
9. send a SS control, SS MMI string or USSD string, indicating which alphabet is used where applicable.
10. play a tone in the appropriate audio device.
11. negotiate, within reasonable tolerances, a periodic "polling" of the USIM Toolkit.
12. refresh the image (if applicable) of the USIM data contained in the ME memory, either entirely, or partially, or instruct the ME to re-initialize completely.
13. set up an event list in the ME such that the UICC is informed by the ME when an indicated event has occurred.
14. set up an additional menu in the ME, by issuing the ME with a menu list, and allow indication back to the UICC of the user selected menu item.
15. provide requested information from the ME to the UICC, for example the MCC, MNC and IMEI.
16. communicate bi-directionally with an auxiliary device, e.g. a second card reader.
17. set up, refresh and interrogate several timers, and inform the UICC when these expire, within reasonable tolerances.
18. display additional MMI information such as display information or tones with commands that employ network resources, with an indication to the ME as to the required level of ME generated MMI as a result of the interaction with the network.
19. allow the ME to display help information with the commands, by providing the associated text, related to the user action (e.g. menu selection).
20. Provide indication from the ME to the USAT when a key on the MMI has been pressed in a "menu" (response to prompt) or and event (independent action) methods, with key identification. This indication shall be done in a secure manner.
21. send a MM to the network, using a data channel as (5) above. The MM content is supplied by the ME or the UICC.
22. start an ME-based application that the USAT application knows about. For example USAT applications have the ability to launch a micro-browser if provided by the ME as already described in this document (see Interactions with MExE), or may ask the ME to initiate a data synchronisation process.
    Note: addressing of ME applications and other relevant parameters if needed, shall be properly defined by the corresponding USAT specifications.
23. Provide location information from the ME to the UICC (e.g. GPS, A-GPS, Galileo, etc) if the ME is equipped with a positioning feature.
24. Provide a list of the CSG identities available application for selection together with the corresponding HNB Names from the ME to the UICC applications, if available to the ME.
25. Inform the UICC applications when selecting and leaving a CSG cell and to provide the corresponding CSG identity and HNB Name, if HNB Name is available.

Unless otherwise stated the following shall apply:

• The format of text to be displayed is designated by the UICC and is either SMS default alphabet (packed or unpacked) or UCS2 alphabet.
• The format of the response from the ME is designated by the UICC and is either keypad digit (0 9, *, #, +), SMS default alphabet characters or UCS2 alphabet characters.

The ME supporting bearer independent protocol shall provide to the USIM a common interface for any type of data bearer. This interface is in addition to dedicated commands (e.g. SMS, SS and USSD) for USAT application to exchange data with entities outside the UICC. The communication is initiated by the UICC. The ME negotiates with the UICC and the addressed entity to establish the optimum channel considering the UICC request, the network and ME capabilities. The ME is responsible for maintaining and restoring the link should there be a link error.

It shall be possible for the UICC to request the current location information from the ME for USAT applications if the ME is equipped with a positioning feature capable of operating in autonomous, MS Assisted or MS Based modes (e.g. GPS, A-GPS, Galileo, etc). It shall be possible for the UICC to detect the presence of a positioning feature in the Terminal Profile if the ME is equipped with a positioning feature. The ME shall inform the UICC if the location feature is disabled when the UICC requests the ME to send the location information. The ME shall inform the UICC if the location information retrieval is not possible (e.g. due to lack of GPS coverage) when the UICC requests the ME to send the location information. The UICC request for location information shall be treated in accordance with the principles defined in TS 22.071.

In order to be able to create and operate applications with a homogeneous display(s) USAT shall fully control the display of all actions and all network-responses concerned with the operation of the application. USAT shall, upon completion/closure of the application, return full control to the ME. The display of information shall be either in the form of text (i.e. alphanumeric characters) or in graphical form or both. Optionally under user control the ME may display the individual actions/network responses.

In order to be able to create and operate applications with a homogeneous user interface USAT shall fully control the function associated with the user input for example via the keypad of the ME. Exceptions to this are keys which are "dedicated ME keys" such as the ON/OFF key. USAT shall, upon completion/closure of the application, return full control to the ME.

A simple, powerful method for the user to access and interact with certain USAT applications shall be provided. It shall be possible for the USAT-Application to set up a user interface (e.g. menu, icons) via the capabilities provided by the ME to allow the user to interact with a USAT application using, for example, the display and keypad.

The soft-key allocation capability is a mechanism whereby the UICC indicates to the ME the text to be displayed and the USAT function which is to be assigned to a ME soft-key.

The user may be able to control the USAT execution environment via the ME in accordance with the following cases:

1. the USAT execution environment is enabled/disabled
2. the USAT execution environment is not allowed to make automatic calls
3. the USAT execution environment is allowed to make automatic calls but only with user confirmation
4. the USAT execution environment is allowed to make automatic calls without user confirmation.

In addition it shall be possible for the user to independently enable/disable the AT command feature. Note that for ease of reading the term "automatic call" is used but this shall be taken to mean any network interaction initiated by USAT including SMS, USSD etc. but excluding user initiated interactions modified by USAT. The user shall be notified by the ME if service access is prevented as the result of partially disabling the USAT execution environment. It shall be possible to enable the USAT execution environment if service access has been prevented.

The USAT shall be able to request the ME to present to the user a Multimedia Message (i.e. via the MMS user agent in the ME) stored in the UICC (see TS 22.140).

USAT/Network interaction is required such that the USAT and the network can bi-directionally exchange data through the ME, employing any of the transport mechanisms defined in the section "USAT data exchange capabilities requirements".

The communication control capability is a mechanism whereby the use of communication resources is either initiated by the USAT application or modified by the USAT application subsequent to a user action. If supported by the ME, the ME shall, at the time of the user initiated communication request, inform the UICC of the current cell location identity. The UICC shall indicate to the ME if the presentation of information (display, tones etc.) shall be restricted to the explicit presentation of USAT supplied information or if it is required to present standard PLMN information (e.g. network responses) in addition to the USAT supplied information. It shall be possible for the UICC:

• to initiate and terminate a (UICC initiated) communication request with or without explicit confirmation by the user
• to allow, bar or modify a communication request initiated by the user
• to replace a user initiated communication request by another communication request (e.g. replace call request by an SS action etc.).

It shall be possible for the SAT/USAT serving environment to enable/disable the communication control capability. As an option, dependant on the subscribers subscription and the application, the user may enable/disable the communication control capability via a SAT/USAT serving environment and/or under the control of the Network Operator. The user shall be notified by the ME in case network service is lost as the result of disabling the communication control capability. The communication control capability applies to all mobile originated requests independent of the applicable data exchange capability. Explicitly it applies to voice calls, IMS based communications and to all services listed in the section "USAT data exchange capabilities requirements" (e.g. SMS, supplementary service, circuit switched connection, packet switched connection, etc.).

The USAT application shall be able to use all PLMN services and supplementary services (SS) including those functions available to the user via the standardized MMI (e.g. 2 SEND for Call Hold). Only the originator (i.e. either user or USAT application) of the action shall directly receive the results/responses of that action (e.g. network response to an SCI). Optionally under user control the ME may display the individual actions/responses.

USAT shall support the transmission (mobile originated) and the reception (mobile terminated) of data by means of one of the following data exchange capabilities, either using dedicated commands or managed by the ME (using the Bearer Independent Protocol);

A major aspect of the UICC is the security provided by the chip technology combined with the encryption and challenge/response procedures. The enhancement of the UICC by USAT shall not reduce nor endanger the current security. In addition, the USAT environment shall maintain (or improve) the same high levels of security. Adequate (future) measures shall be taken to ensure the fulfilment of this requirement also with future advances in technologies/services (either network-centric and/or UE-centric).

This subclause defines the interaction between PLMN supplementary services and the USAT feature. PLMN supplementary services shall not have any knowledge of USAT based services.

USAT shall be able to modify the called number entered by the user.

No interaction.

No interaction.

USAT shall be able to modify the transfer number entered by the user.

USAT shall be able to modify the number displayed to the user.

No interaction.

No interaction.

The SAT/USAT applications have the the ability to launch a micro-browser (on a given URL and a given bearer) if provided by the ME.

No interaction.

Given the wide ranging hardware capabilities of UICCs and MEs, together with the development of USAT applications and applets, a USAT classification shall be supported to determine their respective capability and compatibility. The USAT classification shall apply both to UICCs, MEs and applications and applets. The objective is to:

• classify the requirements of a USAT UICC/applications and
• identify the commands and features supported by the ME

The development and maintenance of the USAT specification is done in accordance to the ETSI/3GPP release procedures. I.e. annual releases of the specifications are done providing support for new commands and enhancements of existing commands. The annual Release may both contain commands that are mandatory for that Release and commands that are optional. The classification of the optional commands and features in a given Release may be done with the concept of "Letter Classes". A Letter Class identifies a subset of functionality of the Release, which will provide the user, USAT serving environment and application writer with a consistent set of commands and features. The concept of a USAT Letter Classes is introduced to help identify the ME, and the UICC /USAT application compatibility within a given Release. The USAT Letter Class is distinct and unrelated to the existing PLMN UE Classmark. The USAT Letter Classes are not used during capability negotiations, but are intended to assist in designing applications by provision of a means for an application designer to identify which combinations of USAT features are supported by the MEs. Capability negotiations between the UICC and the ME are performed at the feature level, independent of the USAT Letter Class. In addition to classifying the ME as conforming to a specific Release and if applicable one or several Letter Classes within the release, an ME manufacturers declaration shall be provided. This shall indicate in detail the commands and features supported by the ME. Any conformance testing shall be performed in accordance to this declaration. The support of a given Letter Class doesn't require the support of another Letter Class. USAT applications will be developed to execute on USAT UE's in one or more classifications. In order for USAT applications to be properly supported by a USAT UE, the application shall be designated by the same classification of USAT UE's on which they are intended to be executed.

In the case of an ME not supporting SAT/USAT or not supporting a certain SAT/USAT feature the following shall apply:

• the USIM shall control (i.e. allow or prevent) the access to the network.
  This allows the USIM to prevent the use of a subscription (which may rely on the support of USAT features for correct operation) in an uncontrolled manner.
• if access to a PLMN is not prevented the ME shall support the non-USAT PLMN features without restriction.

If supported, the UICC and the ME shall exchange USAT capabilities when the card session is initiated. This exchange of information is important since the UICC then knows what the ME is capable of, and the UICC can thus adapt the service made available to the user accordingly. If the UICC does not receive any ME capability information it shall assume that the ME does not support USAT. A UICC that supports USAT shall not attempt to invoke USAT functions in the ME if the ME has not indicated USAT support. An ME that supports USAT shall not attempt to invoke USAT functions in the UICC if the UICC has not indicated that USAT is supported and is active.

For compatibility testing the ME manufacturers shall provide a declaration of the Release and if applicable the Letter Class(es) supported by the ME including the detail of all commands and features supported by the ME. It can be envisaged that ME implementations will exist that are compliant to a given release and which support commands and features from later releases.