26 research outputs found
Can Component/Service-Based Systems Be Proved Correct?
Component-oriented and service-oriented approaches have gained a strong
enthusiasm in industries and academia with a particular interest for
service-oriented approaches. A component is a software entity with given
functionalities, made available by a provider, and used to build other
application within which it is integrated. The service concept and its use in
web-based application development have a huge impact on reuse practices.
Accordingly a considerable part of software architectures is influenced; these
architectures are moving towards service-oriented architectures. Therefore
applications (re)use services that are available elsewhere and many
applications interact, without knowing each other, using services available via
service servers and their published interfaces and functionalities. Industries
propose, through various consortium, languages, technologies and standards.
More academic works are also undertaken concerning semantics and formalisation
of components and service-based systems. We consider here both streams of works
in order to raise research concerns that will help in building quality
software. Are there new challenging problems with respect to service-based
software construction? Besides, what are the links and the advances compared to
distributed systems?Comment: 16 page
Semantic Embedding of Petri Nets into Event-B
We present an embedding of Petri nets into B abstract systems. The embedding
is achieved by translating both the static structure (modelling aspect) and the
evolution semantics of Petri nets. The static structure of a Petri-net is
captured within a B abstract system through a graph structure. This abstract
system is then included in another abstract system which captures the evolution
semantics of Petri-nets. The evolution semantics results in some B events
depending on the chosen policies: basic nets or high level Petri nets. The
current embedding enables one to use conjointly Petri nets and Event-B in the
same system development, but at different steps and for various analysis.Comment: 16 pages, 3 figure
Tool-Assisted Multi-Facet Analysis of Formal Specifications (Using Alelier-B and ProB).
International audienceTool-assisted analysis of software systems and convenient guides to practise the formal methods are still motivating challenges. This article addresses these challenges. We ex periment on analysing a formal specification from multiple aspects. The B method and the Atelier-B tool are used for formal specifications, for safety property analysis and for refinements. The ProB tool is used to supplement the study with model checking; it helps to discover errors and there fore to improve the former specifications
Modelling and Analysing Dynamic Decentralised Systems
We introduce a method to specify and analyse decentralised dynamic systems;
the method is based on the combination of an event-based multi-process system
specification approach with a multi-facet analysis approach that considers a
reference abstract model and several specific ones derived from the abstract
model in order to support facet-wise analysis. The method is illustrated with
the modelling and the analysis of a mobile ad-hoc network. The Event-B
framework and its related tools B4free and ProB are used to conduct the
experiments.Comment: 6 pages - two columns (IEEE) - Conference PRDC'200
Using Event-B to Verify the Kmelia Components and Their Assemblies
International audienceBuilding reliable software systems from components requires to verify the consistency of components and the correctness of component assemblies. In this work, we design a verification method to address the problem of verifying the consistency of components states and the correctness of assembly contracts, using pre-/post-conditions. The starting point is specifications written with the Kmelia component model: a Kmelia component type declares provided and required services which are used to link components in component assemblies. We generate Event-B models from Kmelia specifications in such a way that we can check the consistency and also the correctness of assembly at the Kmelia level, using Event-B provers. An illustrative example based on a stock management system is used to support the presentation
Filtered Comparison for Oracle in ModelTransformation Testing
International audienceFocusing on one part of a produced output helps in improving model transformation testin
A Formal and Tool-Equipped Approach for the Integration of State Diagrams and Formal Datatypes
International audienceSeparation of concerns or aspects is a way to deal with the increasing complexity of systems. The separate design of models for different aspects also promotes a better reusability level. However, an important issue is then to define means to integrate them into a global model. We present a formal and tool-equipped approach for the integration of dynamic models (behaviors expressed using state diagrams) and static models (formal data types) with the benefit to share advantages of both: graphical user-friendly models for behaviors, formal and abstract models for data types. Integration is achieved in a generic way so that it can deal with both different static specification languages (algebraic specifications, Z, B) and different dynamic specification semantic
Combining Techniques to Verify Service-based Components
International audienceEarly verification is essential in model-driven development because late error detection involves a costly correction and approval process. Modelling real life systems covers three aspects of a system (structure, dynamics and functions) and one verification technique is not sufficient to check the properties related to these aspects. Considering Service-based Component Models, we propose a unifying schema called multi-level contracts that enables a combination of verification techniques (model checking, theorem proving and model testing) to cover the V&V requirements. This proposal is illustrated using the Kmelia language and its COSTO tool
Model checking paramétrique statistique du plan de vol de drone civil
International audienceLes drones sont maintenant très répandus dans la société et sont souvent utilisés dans des situations dangereuses pour le public environnant. Il est alors nécessaire d'étudier leur fiabilité, en particulier dans le contexte de vols au-dessus d'un public. Dans cet article, nouś etudions la modélisation et l'analyse de drones dans le contexte de leur plan de vol. Pour cela, nous construisons un modèle probabiliste paramétrique du drone et l'utilisons ainsi que son plan de vol pour modéliser la trajectoire du drone. Ce modèle prend en compte des paramètres comme la défaillanceéventuelle du filtre ou du capteur (comme le GPS), ainsi que la force et la direction du vent. Du fait de la nature et de la complexité des modèles successifs obtenus, leur vérification avec les outils PRISM ou PARAM est impossible. Nous développons donc une nouvelle méthode d'approximation, appelée Parametric Statistical Model Checking, afin de calculer les probabilités de défaillance du drone. Cette méthode aété implémentée dans un prototype, que nous avons utilisé pour résoudre des difficultés complexes dans uneétude de cas réelle