AADLib, A Library of Reusable AADL Models

The SAE Architecture Analysis and Design Language is now a well-established language for the description of critical embedded systems, but also cyber-physical ones. A wide range of analysis tools is already available, either as part of the OSATE tool chain, or separate ones. A key missing elements of AADL is a set of reusable building blocks to help learning AADL concepts, but also experiment already existing tool chains on validated real-life examples. In this paper, we present AADLib, a library of reusable model elements. AADLib is build on two pillars: 1/ a set of ready-to- use examples so that practitioners can learn more about the AADL language itself, but also experiment with existing tools. Each example comes with a full description of available analysis and expected results. This helps reducing the learning curve of the language. 2/ a set of reusable model elements that cover typical building blocks of critical systems: processors, networks, devices with a high level of fidelity so that the cost to start a new project is reduced. AADLib is distributed under a Free/Open Source License to further disseminate the AADL language. As such, AADLib provides a convenient way to discover AADL concepts and tool chains, and learn about its features

From Java to real-time Java : A model-driven methodology with automated toolchain

Real-time systems are receiving increasing attention with the emerging application scenarios that are safety-critical, complex in functionality, high on timing-related performance requirements, and cost-sensitive, such as autonomous vehicles. Development of real-time systems is error-prone and highly dependent on the sophisticated domain expertise, making it a costly process. There is a trend of the existing software without the real-time notion being re-developed to realise real-time features, e.g., in the big data technology. This paper utilises the principles of model-driven engineering (MDE) and proposes the first methodology that automatically converts standard time-sharing Java applications to real-time Java applications. It opens up a new research direction on development automation of real-time programming languages and inspires many research questions that can be jointly investigated by the embedded systems, programming languages as well as MDE communities

Mapping AADL to Petri Net Tool-Sets Using PNML Framework

Architecture Analysis and Design Language (AADL) has been utilized to specify and verify non- functional properties of Real-Time Embedded Systems (RTES) used in critical application systems. Examples of such critical application systems include medical devices, nuclear power plants, aer- ospace, financial, etc. Using AADL, an engineer is enable to analyze the quality of a system. For example, a developer can perform performance analysis such as end-to-end flow analysis to guarantee that system components have the required resources to meet the timing requirements relevant to their communications. The critical issue related to developing and deploying safety critical systems is how to validate the expected level of quality (e.g., safety, performance, security) and functionalities (capabilities) at design level. Currently, the core AADL is extensively applied to analyze and verify quality of RTES embed in the safety critical applications. The notation lacks the formal semantics needed to reason about the logical properties (e.g., deadlock, livelock, etc.) and capabilities of safety critical systems. The objective of this research is to augment AADL with exit- ing formal semantics and supporting tools in a manner that these properties can be automatically verified. Toward this goal, we exploit Petri Net Markup Language (PNML), which is a standard act- ing as the intermediate language between different classes of Petri Nets. Using PNML, we interface AADL with different classes of Petri nets, which support different types of tools and reasoning. The justification for using PNML is that the framework provides a context in which interoperability and exchangeability among different models of a system specified by different types of Petri nets is possible. The contributions of our work include a set of mappings and mapping rules between AADL and PNML. To show the feasibility of our approach, a fragment of RT-Embedded system, namely, Cruise Control System has been used

Towards a formal semantics for AADL execution model

International audienceIn this paper, we present a specification in TLA+ of an AADL execution model. This formal specification is used forderiving a prototype verification tool for AADL the TOPCASED development environment

Un meta-modèle de composants pour la réalisation d'applications temps-réel flexibles et modulaires

The increase of software complexity along the years has led researchers in the software engineering field to look for approaches for conceiving and designing new systems. For instance, the service-oriented architectures approach is considered nowadays as the most advanced way to develop and integrate fastly modular and flexible applications. One of the software engineering solutions principles is re-usability, and consequently generality, which complicates its appilication in systems where optimizations are often used, like real-time systems. Thus, create real-time systems is expensive, because they must be conceived from scratch. In addition, most real-time systems do not beneficiate of the advantages which comes with software engineering approches, such as modularity and flexibility. This thesis aim to take real time aspects into account on popular and standard SOA solutions, in order to ease the design and development of modular and flexible applications. This will be done by means of a component-based real-time application model, which allows the dynamic reconfiguration of the application architecture. The component model will be an extension to the SCA standard, which integrates quality of service attributs onto the service consumer and provider in order to stablish a real-time specific service level agreement. This model will be executed on the top of a OSGi service platform, the standard de facto for development of modular applications in Java.La croissante complexité du logiciel a mené les chercheurs en génie logiciel à chercher des approcher pour concevoir et projéter des nouveaux systèmes. Par exemple, l'approche des architectures orientées services (SOA) est considérée actuellement comme le moyen le plus avancé pour réaliser et intégrer rapidement des applications modulaires et flexibles. Une des principales préocuppations des solutions en génie logiciel et la réutilisation, et par conséquent, la généralité de la solution, ce qui peut empêcher son application dans des systèmes où des optimisation sont souvent utilisées, tels que les systèmes temps réels. Ainsi, créer un système temps réel est devenu très couteux. De plus, la plupart des systèmes temps réel ne beneficient pas des facilités apportées par le genie logiciel, tels que la modularité et la flexibilité. Le but de cette thèse c'est de prendre en compte ces aspects temps réel dans des solutions populaires et standards SOA pour faciliter la conception et le développement d'applications temps réel flexibles et modulaires. Cela sera fait à l'aide d'un modèle d'applications temps réel orienté composant autorisant des modifications dynamiques dans l'architecture de l'application. Le modèle de composant sera une extension au standard SCA qui intègre des attributs de qualité de service sur le consomateur et le fournisseur de services pour l'établissement d'un accord de niveau de service spécifique au temps réel. Ce modèle sera executé sur une plateforme de services OSGi, le standard de facto pour le developpement d'applications modulaires en Java

Translation Of AADL To PNML To Ensure The Utilization Of Petri Nets

Architecture Analysis and Design Language (AADL), which is used to design and analyze software and hardware architectures of embedded and real-time systems, has proven to be a very efficient way of expressing the non-functional properties of safety-critical systems and architectural modeling. Petri nets are the graphical and mathematical modeling tools used to describe and study information processing systems characterized as concurrent and distributed. As AADL lacks the formal semantics needed to show the functional properties of such systems, the objective of this research was to extend AADL to enable other Petri nets to be incorporated into Petri Net Markup Language (PNML), an interchange language for Petri nets. PNML makes it possible to incorporate different types of analysis using different types of Petri net. To this end, the interchange format Extensible Markup Language (XML) was selected and AADL converted to AADL-XML (the XML format of AADL) and Petri nets to PNML, the XML-format of Petri nets, via XSLT script. PNML was chosen as the transfer format for Petri nets due to its universality, which enables designers to easily map PNML to many different types of Petri nets. Manual conversion of AADL to PNML is error-prone and tedious and thus requires automation, so XSLT script was utilized for the conversion of the two languages in their XML format. Mapping rules were defined for the conversion from AADL to PNML and the translation to XSLT automated. Finally, a PNML plug-in was designed and incorporated into the Open Source AADL Tool Environment (OSATE)

Actes de l'Ecole d'Eté Temps Réel 2005 - ETR'2005

Pdf des actes disponible à l'URL http://etr05.loria.fr/Le programme de l'Ecole d'été Temps Réel 2005 est construit autour d'exposés de synthèse donnés par des spécialistes du monde industriel et universitaire qui permettront aux participants de l'ETR, et notamment aux doctorants, de se forger une culture scientifique dans le domaine. Cette quatrième édition est centrée autour des grands thèmes d'importance dans la conception des systèmes temps réel : Langages et techniques de description d'architectures, Validation, test et preuve par des approches déterministes et stochastiques, Ordonnancement et systèmes d'exploitation temps réel, Répartition, réseaux temps réel et qualité de service

Une approche intégrée pour la validation et la génération de systèmes critiques par raffinement incrémental de modèles architecturaux

The increasing complexity of distributed realtime and embedded (DRE) systems and their implication in various domains imply new design and development methods. In safety- criticial domains such as space, aeronautical, transport or medicine, their failure could result in the failure of the mission, or in dramatic damages such as human losses. This particular class of systems comes with strong requirements to satisfy safety, reliability and security properties. The Model-driven Engineering (MDE) introduces the concept of «model» - an abstract description of the system and a set of tools (editor, transformation engine, code generator) to simplify and automatize the design, the validation and the implementation of the system. Thus, various abstractions are realized using different domain-specific modeling languages in order to assess one particular aspect of the system and to re-use model-based analysis tools and generative technologies. These various representations may share some commonalities but the consistency between them is hard to validate (for example : Is the analyzed system the same as the generated one ?).This PhD thesis leverages MDE concepts and mechanisms, to enhance the reliability of the model-based development process of DRE systems. Our approach is based on the definition of the architectural and behavioral modeling language AADLHI Ravenscar, a restriction of AADL (Architecture Analysis & Design Language) and its behavioral annex. This subset of AADL constructs, comes up with a semantic close to the one of an imperative programming language, to drive both the analysis and the code generation of the application components and its relying execution platform (middleware) components...L’augmentation de la complexité des systèmes temps-réel répartis embarqués (TR2E) et leur implication dans de nombreux domaines de notre quotidien imposent de nouvelles mé thodes de réalisation. Dans les domaines dits critiques (transport, médecine...) ces systèmes doivent satisfaire des contraintes dures pour garantir leur bon fonctionnement et éviter toutes défaillances qui engendreraient des conséquences financières ou humaines dramatiques. L’Ingénierie Dirigée par les Modèles (IDM) introduit le “modèle” - i.e. une description abstraite du système - et un ensemble d’outils (édition, transformation...) permettant la simplification et l’automatisation des étapes de conception, de validation et de génération du système. Ainsi, différentes abstractions du système sont élaborées dans des formalismes spécifiques de manière à couvrir un aspect du système et à permettre la réutilisation des outils d’analyse et de génération existants. Cependant, ces multiples représentations évoluent à des niveaux d’abstractions différents et il n’est pas toujours évident de mettre en corrélation système analysé et système généré. Ce travail de thèse exploite les concepts et les mécanismes offerts par l’IDM pour améliorer la fiabilité du processus de réalisation des systèmes critiques basé sur les modèles. L’approche que nous avons définie repose sur la définition du langage de modélisation architecturale et comportementale AADL-HI Ravenscar - un sous-ensemble du langage AADL (Architecture Analysis & Design Language) et de son annexe comportementale - contraint pour permettre conjointement l’analyse et la génération de l’ensemble des composants de l’application y compris de son exécutif, avec une sémantique proche d’un langage de programmation impératif..