CAT/STK validator

CAT/STK is an interactive tool in hands of MNOs for delivering value-added services like extra-paid messages, mobile banking, etc (to subscribers) [wiki].

CAT/STK validator is a tool to automate the process of validating CAT/STK implementation on SIM/USIM cards and the back-end OTA infrastructure. It is aimed at Mobile Network Operators as well as UICC card manufacturers.

CAT/STK validator was developed for one of the biggest Mobile Network Operators in Poland. It was created in order to make the process of introducing new UICC modules (commonly known as SIM cards) into the market faster while strenghtening quality control. By doing that, the overall time required for quality control over new card products was reduced from five to roughly one single day.

CAT/STK validator was developed according to ETSI TS 102 223 Smart Cards; Card Application Toolkit (CAT) specification.

CAT/STK validator In Action

Process Improvements

Validation process offered by the tool is designed to mimic quality control check performed by a human operator with the usual benefits of automation:
  • much faster operation,
  • unparalleled reliability,
  • rapid error reporting,
  • 100% compliance with expected results.

UICC undergoes validation process in a production environment – all operations are performed in a live network using real device and MNO's production back-end Over-The-Air service.

While being validated, the UICC is plugged into a mobile phone. Phone's modem provides UICC with network access, therefore a subscription has to be assigned temporarily to that UICC.

The mobile phone to which the UICC is plugged into, has to be run under control of a custom version of Android OS (which is provided as a core component of the CAT/STK validator).

Reliability of Instrumentation

Validation scenarios are described by means of XML files. Each XML file can contain indefinite number of items constituting multiple validation scenarios. Validation scenarios define complete spectrum of CAT/STK implementation details defined by the specification, such as:
  • layout of expected list menus,
  • layout of input menus,
  • content of expected text messages,
  • identificators of tones to be played and their configuration,
  • references to bitmaps to be displayed,
  • configuration of web browser to be started,
  • configuration of voice calls to be dialled,
  • specification of time duration to be expected,
  • specification of requested font sizes, types, arguments and colors.

Each validation scenario is a series of:
  • actions to perform on the CAT/STK implementation,
  • expected CAT/STK reactions presented to the user interface.
If the obtained reaction is not consistent with the scenario, the validation process is interrupted and the failure is communicated with all the details required to locate and reproduce the problem.

On a more abstract layer, CAT/STK validator can offer following functionalities:
  • complete interaction with each type of CAT/STK input and output according to XML scenarios, such as:
    • input values into input-requesting menu,
    • click chosen item/button,
    • validate text presented to the user,
    • validate bitmap icon presented to the user,
    • validate tone playback request;
  • running complete suite of scenarios,
  • running chosen scenarios on demand,
  • storing and presenting validation results,
  • smart adaptation to time-differing back-end responses due to network load.

XML test scenarios guarantee required flexibility and update/modify simplicity to satisfy the needs of fast and painless introduction of new card products into the market.

The Design

CAT/STK validator consists of three parts:
  • UICC with CAT/STK implementation undergoing validation process,
  • mobile device:
    • provides SIM/UICC network access to MNO back-end infrastructure,
    • serves as a proxy between instrumentator and the UICC;
  • PC instrumentator/validator connected logically to the mobile device:
    • makes use of validation scenarios in XML files,
    • provides User Interface for managing the validation process.

The Product

Polishcode provides CAT/STK validator in two variants:
  • with the mobile device running custom Android OS,
  • without the mobile device, with custom Android OS as a binary for on-site loading onto a production device.

More Info

For detailed info and pricing please see contact page.


STK – SIM Application Toolkit
CAT – Card Application Toolkit
ETSI – European Telecommunications Standards Institute
SIM – Subscriber Identity|Identification Module
USIM – Universal Subscriber Identity Module
UICC – Universal Integrated Circuit Card
RIL – Radio Interface Layer
OTA – Over The Air
MNO – Mobile Network Operator
XML – Extensible Markup Language
PC – Personal Computer


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