1,721,107 research outputs found
Synthesis Of Distributed Adaptors To Enforce Temporal Properties Specified Through Graphical Scenarios
No full textBuilding a distributed system from third-party black-box components introduces a set of prob- lems, mainly related to interoperability. Our previous approach to solve such problems was to build a centralized adaptor which restricts the system’s behavior to exhibit only deadlock- free and desired interactions. However, in a distributed environment such an approach is not always suitable. In this thesis we show how to automatically synthesize a distributed adap- tor for a set of black-box components. As first step, by taking into account a specification of the interaction behavior of each component, we synthesize a behavioral model of a centralized glue adaptor. As second step, from the synthesized adaptor model and a specification of the desired interaction behavior that must be guaranteed, we generate one local adaptor for each component. The local adaptors suitably communicate in order to avoid possible deadlocks and to enforce the specified desired interaction behavior. These local adaptors constitute the dis- tributed adaptor for the given set of black-box components. The desired interaction behavior is specified through an LTS-based notation. This notation has a simple enriched syntax for easily specifying a relevant subset (i.e., regular expressions) of all possible interactions specifiable by more expressive temporal logic based formalisms (such as Linear-time Temporal Logic). In this thesis we also propose a formalism for specifying temporal properties aimed at being simple, (sufficiently) powerful and user-friendly. After examining Message Sequence Charts, and UML 2.0 Interaction Sequence Diagrams, we present a scenario-based graphical language that is an extended notation of a selected subset of the UML 2.0 Interaction Sequence Diagrams. This language is called Property Sequence Chart (PSC) and represents a first step toward languages that try to balance expressive power and simplicity of use. By means of PSC more complex desired/undesired interaction behaviors can be specified w.r.t. the ones specifiable through the LTS-based notation used by the approach to the automatic synthesis of distributed adaptors
Towards a Graphical Tool for Refining User to System Requirements
No full textAbstractInformal and abstract user requirement specifications are usually complemented by formal and detailed system requirement specifications. While user requirements provide a high level description of what services the system is expected to provide, system requirements provide a more technical specification of how that services should be provided by the system. One of the relevant problems that arise during the Requirement Engineering process is the result of failing to make a clear transition between different levels of requirements description.Goal of this paper is to introduce a graphical tool for requirements refinement which guides software architects while moving from user requirements to (architec-tural-level) system requirements. The tool makes use of a previous work that gives a simple but expressive graphical formalism, based on UML2.0 Sequence Diagrams, for specifying temporal properties
Thematic series on Verification and Composition for the Internet of Services and Things
No full textThe Internet of Services and Things is characterized as a distributed computing environment that will be populated by a large number of software services and things. Within this context, software systems will increasingly be built by reusing and composing together software services and things distributed over the Internet. This calls for new integration paradigms and patterns, formal composition theories, integration architectures, as well as flexible and dynamic composition and verification mechanisms. In particular, service- and thing-based systems pose new challenges for software composition and verification techniques, due to changing requirements, emerging behaviors, uncertainty, and dynamicity
Distributed Enforcement of Service Choreographies
No full textModern service-oriented systems are often built by reusing, and composing together, existing services distributed over the Internet. Service choreography is a possible form of service composition whose goal is to specify the interactions among participant services from a global perspective. In this paper, we formalize a method for the distributed and automated enforcement of service choreographies, and prove its correctness with respect to the realization of the specified choreography. The formalized method is implemented as part of a model-based tool chain released to support the development of choreography-based systems within the EU CHOReOS project. We illustrate our method at work on a distributed social proximity network scenario
A Multipurpose Framework for Model-based Reuse-oriented Software Integration Synthesis
No full textSystems are increasingly built by reusing and integrating existing software. This paper presents the preliminary version of a multipurpose framework for software integration synthesis. The objective is to provide both researchers and practitioners with an easily accessible environment that, integrating different kinds of software synthesizers, permit to perform different kinds of analyses, verification, model-to-model and model-to-code transformations, all oriented to the reuse and the integration of existing, possibly third-party, software
Towards Self-evolving Context-aware Services
Full text linkThe introduction of new communication infrastructures such as Beyond 3rd Generation
(B3G) and the widespread usage of small computing devices are rapidly
changing the way we use and interact with technology to perform everyday tasks.
Ubiquitous networking empowered by B3G networking makes it possible for mobile
users to access networked software services across continuously changing heterogeneous
infrastructures by resource-constrained devices. Heterogeneity and devices'
limitedness, create serious problems for the development and dynamic deployment
of mobile applications that are able to run properly on the execution context and
consume services matching with the users' expectations. Furthermore, the everchanging
B3G environment calls for applications that self-evolve according to context
changes. Out of these problems, self-evolving adaptable applications are increasingly
emerging in the software community. In this paper we describe how
CHAMELEON, a declarative framework for tailoring adaptable applications, is being
used for tackling adaptation and self-evolution within the IST PLASTIC project
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