Dragos Truscan

Tool support for DFD-UML model-based transformations

This paper presents a model-based approach that combines the data-flow and object-oriented computing paradigms to model embedded systems. The rationale behind the approach is that both views are important for modelling purposes in embedded systems environments, and thus a combined and integrated usage is not only useful, but also fundamental for developing complex systems. We also show that by using models we are able to implement automated transformations between different views of the system under design. We exemplify the approach with an IPv6 router case study.

A Model-Based Design Process for the SegBus Distributed Architecture

We discuss a design process for a custom distributed platform, namely the SegBus segmented bus architecture. The main emphasis of this work is on how different steps of the process are interconnected and how they are supported by the associated tool chain. We place the SegBus design process in the context of the model-driven architecture (MDA) paradigm, in order to provide graphical editors that allow the editing of the specification at different abstraction levels and automated transformations that refine the specification towards implementation. We customize the Unified Modeling Language (UML) to graphically specify different artifacts produced in the process and we employ UML-based tools to implement transformations between these artifacts. In addition, we adopt as application model the packet SDF (PSDF), an extension of the synchronous data flow (SDF) diagrams. By modeling the operational semantics for the SegBus architecture, the PSDF facilitates the mapping of the application on the architecture. From the mapping process we obtain the requirements for the structural VHDL code of the application-platform instance realization and the control code for the arbiters of the architecture.

Model-based performance testing in the cloud using the mbpet tool

In this paper, we present an approach for performance testing of software services. In our approach, we use Probabilistic Timed Automata (PTA) to model the workload of the system, by describing how different user types interact with the system. We use these models to generate load in real-time and we measure different performance indicators. An in-house developed tool, MBPeT, is used to support our approach. We exemplify with an auction web service case study and show how performance information about the system under test can be collected.

Using UML Models and Formal Verification in Model-Based Testing

In this paper we present a model-based testing approach where we integrate UML, UML-B and the Qtronic test generator tool, with the purpose of increasing the quality of models used for test generation via formal verification. The architectural and behavioral models of the system under test (SUT) are specified in UML and UML-B, respectively. UMLB provides UML-like visualization with precise mathematical semantics. UML-B models are developed in a stepwise manner which are then automatically translated into Event-B specifications that can be proved using theorem provers. Once the formal models are proved, they are transformed into QML which is a modeling language used by the test generation tool.

Tracing Requirements in a Model-Based Testing Approach

In this paper we discuss an approach for requirements traceability in a model-based testing process. We show how the informal requirements of the system under test evolve and are traced at different steps of the process. More specifically, we discuss how requirements are traced to system specifications and from system specification to tests during the test generation process, and then how the test results are analyzed and traced back the specification of the system. The approach allows us to have both a fast feed-back loop for debugging either the specification or the implementation of the system and a way to estimate the coverage degree of the generated tests with respect to requirements. We discuss tool support for the approach and exemplify with excerpts from a case study in the telecommunications domain.

Model-Based Testing Using System vs. Test Models - What Is the Difference?

We discuss the differences between using system models and test models with respect to the model-based testing process. Although these two terms are usually used interchangeably, very little is known about the distinction between the two. System models describe internal behavior of the system under test while the test models contain the behavior from user’s or environment’s point of view. We describe how these two types of models are obtained and used throughout the model-based testing process and how they are related to each other. The discussion is based on our earlier experiences as well as on two case study examples from the telecommunication domain.

MATERA - An Integrated Framework for Model-Based Testing

This paper presents MATERA, a framework that integrates modeling in the Unified Modeling Language (UML), with requirement traceability across a model-based testing (MBT) process. The Graphical User Interface (GUI) of MATERA is implemented as a plug-in in the NoMagics MagicDraw modeling tool, combining existing capabilities of MagicDraw with custom ones. MATERA supports graphical specification of the requirements using SysML and tracing of them to the UML models specifying the SUT. Model validation is performed in MagicDraw using both predefined and custom validation rules. The resulting models are automatically transformed into input for the Conformiq Qtronic tool, used for automated test generation. Upon executing the test scripts generated by Qtronic in the NetHawks East execution environment, the results of statistic analysis of the test run are presented in the GUI. The back-traceability of the covered requirements from test to models is also provided in the GUI to facilitate the identification of the source of possible errors in the models. The approach we present shows that existing model-based languages and tools are an enabler for model-based testing and for providing integrated tool support across the MBT process.

Testable Specifications of NoTA-based Modular Embedded Systems

We propose an approach to specifying embedded devices based on the Network on Terminal Architecture (NoTA) and show how the approach allows the specification of NoTA components, including service interfaces, and timing and energy consumption constraints. The purpose of such specifications is two fold: to enable vendors to provide already tested component implementations with respect to specifications, and to allow system designers to test these components in integration. The proposed specifications feature both a graphical notation for facilitating the specification process using dedicated tools and a textual one for exchanging component specifications between system designers and vendors.

Integration of DFDs into a UML-based model-driven engineering approach

The main aim of this article is to discuss how the functional and the object-oriented views can be inter-played to represent the various modeling perspectives of embedded systems. We discuss whether the object-oriented modeling paradigm, the predominant one to develop software at the present time, is also adequate for modeling embedded software and how it can be used with the functional paradigm. More specifically, we present how the main modeling tool of the traditional structured methods, data flow diagrams, can be integrated in an object-oriented development strategy based on the unified modeling language. The rationale behind the approach is that both views are important for modeling purposes in embedded systems environments, and thus a combined and integrated model is not only useful, but also fundamental for developing complex systems. The approach was integrated in a model-driven engineering process, where tool support for the models used was provided. In addition, model transformations have been specified and implemented to automate the process. We exemplify the approach with an IPv6 router case study.

A Brunch from the Coffee Table-Case Study in NoC Platform Design

Tapani Ahonen*, Seppo Virtanen**, Juha Kylliäinen*, Dragos Truscan***, Tuukka Kasanko*, David Sigüenza-Tortosa*, Tapio Ristimäki*, Jani Paakkulainen**, Tero Nurmi**, Ilkka Saastamoinen*, Hannu Isännäinen*, Johan Lilius***, Jari Nurmi*, and Jouni Isoaho** *Institute of Digital and Computer Systems, Tampere University of Technology, Finland **Department of Information Technology, University of Turku, Finland ***Department of Computer Science, Åbo Akademi University, Finland