Using formal methods to support testing

Formal methods and testing are two important approaches that assist in the development of high quality software. While traditionally these approaches have been seen as rivals, in recent years a new consensus has developed in which they are seen as complementary. This article reviews the state of the art regarding ways in which the presence of a formal specification can be used to assist testing

Program Transformation for Development, Verification, and Synthesis of Software

In this paper we briefly describe the use of the program transformation methodology for the development of correct and efficient programs. We will consider, in particular, the case of the transformation and the development of constraint logic programs

A Modular Toolkit for Distributed Interactions

We discuss the design, architecture, and implementation of a toolkit which supports some theories for distributed interactions. The main design principles of our architecture are flexibility and modularity. Our main goal is to provide an easily extensible workbench to encompass current algorithms and incorporate future developments of the theories. With the help of some examples, we illustrate the main features of our toolkit.Comment: In Proceedings PLACES 2010, arXiv:1110.385

Specifying and reasoning about concurrent systems in logic

Imperial Users onl

Strategies for conformance testing

A new test generation method and algorithm for conformance testing is proposed. It is based on the interpretation of testing concepts from the ISO standard ``Formal methods in conformance testing'' in a game theory setting. A testing game is defined with a specification given as an Input/Output State Machine and a test purpose for test selection. A winning strategy for this game define a tester for a class of implementations and a conformance relation. \begin{keywords} formal methods in conformance testing, test purposes, games strategies, test assumptions, input-output state machines. \end{keywords

QoS-Aware Middleware for Web Services Composition

The paradigmatic shift from a Web of manual interactions to a Web of programmatic interactions driven by Web services is creating unprecedented opportunities for the formation of online Business-to-Business (B2B) collaborations. In particular, the creation of value-added services by composition of existing ones is gaining a significant momentum. Since many available Web services provide overlapping or identical functionality, albeit with different Quality of Service (QoS), a choice needs to be made to determine which services are to participate in a given composite service. This paper presents a middleware platform which addresses the issue of selecting Web services for the purpose of their composition in a way that maximizes user satisfaction expressed as utility functions over QoS attributes, while satisfying the constraints set by the user and by the structure of the composite service. Two selection approaches are described and compared: one based on local (task-level) selection of services and the other based on global allocation of tasks to services using integer programming

Synthesis of Distributed Testers from True-concurrency Models of Reactive Systems

Automatic synthesis of test cases for conformance testing has been principall- y developed with the objective of generating sequential test cases. In the distributed system context, it is worth extending the synthesis techniques to the generation of multiple testers. We base our work on our experience in using model-checking techniques, as successfully implemented in the TGV tool. Continuing the works of A. Ulrich and H. König, we propose to use a true-concurrency model based on graph unfolding. The article presents the principles of a complete chain of synthesis, starting from the definition of test purposes and ending with a projection onto a set of testers

Synthesis of Distributed Testers from True-concurrency Models of Reactive Systems

Automatic synthesis of test cases for conformance testing has been principall- y developed with the objective of generating sequential test cases. In the distributed system context, it is worth extending the synthesis techniques to the generation of multiple testers. We base our work on our experience in using model-checking techniques, as successfully implemented in the TGV tool. Continuing the works of A. Ulrich and H. König, we propose to use a true-concurrency model based on graph unfolding. The article presents the principles of a complete chain of synthesis, starting from the definition of test purposes and ending with a projection onto a set of testers

Business Process Variability:a study into process management and verification

Business process management (BPM) beheert en optimaliseert bedrijfsprocessen met het doel om productiviteit en bedrijfsprestaties te verhogen. BPM is een snel evoluerend veld door nieuw opkomende vereisten vanuit flexibele bedrijfstakken waar bedrijfsprocessen steeds minder star behoren te zijn. Waar BPM in het verleden specifieke rigide en repetitieve werkeenheden ondersteunde voor de lokale gebruiker, wordt tegenwoordig vereist dat het losgekoppelde processen ondersteunt in cloud configuraties, te midden van vele gebruikers met elk vele verschillende eisen.Zolang het BPM veld een stijgend aantal snel evoluerende bedrijfsprocessen in flexibele bedrijfstakken ondersteunt, moet de evolutie van elk bedrijfsproces aanhoudend correct gedrag vertonen en tevens voldoen aan de opgelegde wet- en regelgeving en interne bedrijfsregels. Om het aanhoudend correct gedrag te ondersteunen van snel evoluerende BP, of de definitie van een breed aantal soortgelijke bedrijfsprocessen, evalueren we de toepassing van formele verificatietechnieken als mogelijke oplossing voor analyse van het juiste gedrag en wettelijk conforme ontwerp van bedrijfsprocessen binnen mogelijke proces families, welke plaatsvindt voorafgaand aan de uitvoering van dat bedrijfsproces.Een innovatieve benadering voor verificatie tijdens de ontwerpfase wordt gepresenteerd. De benadering ondersteunt de verschillende vertakkende en samenvoegende constructies zoals toegestaan in bedrijfsprocesmodellen en hun service composities. Evaluaties met betrekking tot expressiviteit bewijzen dat, anders dan doorgaans toegepaste transitiesystemen, het voorgestelde model bekende bedrijfsprocespatronen juist vastlegt. Verder behoudt het model informatie over de aanwezigheid van parallelle activiteiten en de lokale volgende activiteit: een eigenschap uniek aan de voorgestelde aanpak.Business Process Management (BPM) manages and optimizes business processes with the intent to increase productivity and performance. BPM is a rapidly evolving field due to new requirements emerging at agile branches of business where business processes are required to be less and less rigid. Where BPM supported local user-specific rigid and repetitive units of work in the past, these days it is required to support loosely-coupled processes in cloud configurations among many users with each many different requirements.As the field of BPM continues to manage an increasing number of rapidly evolving business processes in agile environments, the evolution of each business process must continue to always behave in a correct manner and remain compliant with the laws, regulations, and internal business requirements imposed upon it. To manage the correct behavior of quickly evolving business processes, or the definition of a wide variety of similar business processes, we evaluate the application of formal verification techniques as a possible solution for the pre-runtime analysis of the correct behavior and compliant design of business processes within possible process families. A novel approach allowing pre-runtime verification that supports the different branching and merging constructs allowed by business process models and their service compositions is presented. Evaluations on expressive power demonstrate that, other than the generally employed transition systems, the proposed model correctly captures well-known business process patterns. Furthermore, it maintains information on parallel occurrences of activities and the local next activity occurrence: an ability which is unique to the presented approach