Testing real-time systems using TINA

The paper presents a technique for model-based black-box conformance testing of real-time systems using the Time Petri Net Analyzer TINA. Such test suites are derived from a prioritized time Petri net composed of two concurrent sub-nets specifying respectively the expected behaviour of the system under test and its environment.We describe how the toolbox TINA has been extended to support automatic generation of time-optimal test suites. The result is optimal in the sense that the set of test cases in the test suite have the shortest possible accumulated time to be executed. Input/output conformance serves as the notion of implementation correctness, essentially timed trace inclusion taking environment assumptions into account. Test cases selection is based either on using manually formulated test purposes or automatically from various coverage criteria specifying structural criteria of the model to be fulfilled by the test suite. We discuss how test purposes and coverage criterion are specified in the linear temporal logic SE-LTL, derive test sequences, and assign verdicts

Essay on Semantics Definition in MDE. An Instrumented Approach for Model Verification

International audienceIn the context of MDE (Model-Driven Engineering), our objective is to define the semantics for a given DSL (Domain Specific Language) either to simulate its models or to check properties on them using model-checking techniques. In both cases, the purpose is to formalize the DSL semantics as it is known by the DSL designer but often in an informal way. After several experiments to define operational semantics on the one hand, and translational semantics on the other hand, we discuss both approaches and we specify in which cases these semantics seem to be judicious. As a second step, we introduce a pragmatic and instrumented approach to define a translational semantics and to validate it against a reference operational semantics expressed by the DSL designer. We apply this approach to the xSPEM process description language in order to verify process models

A Generic Tool for Tracing Executions Back to a DSML's Operational Semantics

International audienceThe increasing complexity of software development requires rigorously defined domain specific modeling languages (DSML). Model-driven engineering (\mde) allows users to define a DSML's syntax in terms of metamodels. The behaviour of a language can also be described, either operationally, or via transformations to other languages (e.g., by code generation). If the first approach requires to redefine analysis tools for each DSML (simulator, model-checker...), the second approach allows to reuse existing tools in the targeted language. However, the second approach (also called translational semantics) imply that the results (e.g., a program crash log, or a counterexample returned by a model checker) may not be straightforward to interpret by the users of a DSML. We propose in this paper a generic tool for formally tracing such analysis/execution results back to the original DSML's syntax and operational semantics, and we illustrate it on xSPEM, a timed process modeling language

Ladder Metamodeling & PLC Program Validation through Time Petri Nets

International audienceLadder Diagram (LD) is the most used programming language for Programmable Logical Controllers (PLCs). A PLC is a special purpose industrial computer used to automate industrial processes. Bugs in LD programs are very costly and sometimes are even a threat to human safety. We propose a model driven approach for formal verification of LD programs through model-checking. We provide a metamodel for a subset of the LD language. We define a time Petri net (TPN) semantics for LD programs through an ATL model transformation. Finally, we automatically generate behavioral properties over the LD models as LTL formulae which are then checked over the generated TPN using the model-checkers available in the Tina toolkit. We focus on race condition detection. This work is supported by the topcased project, part of the french cluster Aerospace Valley (granted by the french DGE), cf. http://www.topcased.or

Complex Event Processing Modeling by Prioritized Colored Petri Nets

Complex event processing (CEP) is a technology that allows us to process and correlate large volumes of data by using event patterns, aiming at promptly detecting specific situations that could require special treatment. The event types and event patterns for a particular application domain are implemented by using an event processing language (EPL). Although some current model-driven tools allow end users to easily define these patterns, which are then transformed automatically into a particular EPL, the generated code is syntactically but not semantically validated. To deal with this problem, a prioritized colored Petri net (PCPN) model for CEP is proposed and conducted in this paper. This well-known graphical formalism together with CPNTools makes possible the modeling, simulation, analysis, and semantic validation of complex event-based systems. To illustrate this approach, a case study is presented, as well as a discussion on the benefits from using PCPN for modeling CEP-based systems.El procesamiento de eventos complejos (CEP) es una tecnología que nos permite procesar y correlacionar grandes volúmenes de datos utilizando patrones de eventos, con el objetivo de detectar rápidamente situaciones específicas que podrían requerir un tratamiento especial. Los tipos de eventos y patrones de eventos para un dominio de aplicación particular se implementan utilizando un lenguaje de procesamiento de eventos (EPL). Aunque algunas herramientas actuales impulsadas por modelos permiten a los usuarios finales definir fácilmente estos patrones, que luego se transforman automáticamente en un EPL particular, el código generado se valida sintácticamente pero no semánticamente. Para abordar este problema, en este documento se propone y lleva a cabo un modelo de red de Petri coloreada y priorizada (PCPN) para CEP. Este formalismo gráfico bien conocido junto con CPNTools hace posible la modelización, simulación, análisis y validación semántica de sistemas basados en eventos complejos. Para ilustrar este enfoque, se presenta un estudio de caso, así como una discusión sobre los beneficios de usar PCPN para modelar sistemas basados en CEP.This work was supported in part by the Spanish Ministry of Science and Innovation and the European Union FEDER Funds with the Project DArDOS entitled Formal development and analysis of complex systems in distributed contexts: foundations, tools and applications under Grant TIN2015-65845-C3, subprojects 2-R and 3-R, and the Research Network on Services Science and Engineering under Grant TIN2014-53986-REDT, and in part by the University of Cádiz under Project PR2016-032