Formal aspects of component software

This is the pre-proceedings of 6th International Workshop on Formal Aspects of Component Software (FACS'09)

Formal aspects of component software (FACS 2010 selected and extended papers)

This issue includes extended versions of selected best papers from the 7th International Workshop on Formal Aspects of Component Software (FACS 2010) held in Guimarães, Portugal on October 14–16, 2010. The component-based software development approach has emerged as a promising paradigm to cope with an ever increasing complexity of present-day software solutions by bringing sound production and engineering principles into software engineering. However, many conceptual and technological issues remain that challenge component-based software development theory and practice. To address these issues, FACS seeks to provide a forum for researchers and practitioners in the areas of component software and formal methods to foster a better understanding of the component-based paradigm and its applications as well as how formal methods can or should be used to make component-based software development succeed

Special Issue on Formal Aspects of Component Software (Selected Papers from FACS'12)

International audienceThis issue contains extended versions of selected papers from the 9th International Symposium on Formal Aspects of Component Software (FACS'12)

Component-based modeling and observer-based verification for railway safety-critical applications

1th International Symposium on Formal Aspects of Component Software , Bertinoro, Italie, 10-/09/2014 - 12/09/2015International audienceOne of the challenges that engineers face, during the development process of safety-critical systems, is the verification of safety application models before implementation. Formalization is important in order to verify that the design meets the specified safety requirements. In this paper, we formally describe the set of transformation rules, which are defined for the automatic transformation of safety application source models to timed automata target models. The source models are based on our domain-specific component model, named SARA, dedicated to SAfety-critical RAilway control applications. The target models are then used for the observer-based verification of safety requirements. This method provides an intuitive way of expressing system properties without requiring a significant knowledge of higher order logic and theorem proving, as required in most of existing approaches. An experimentation over a chosen benchmark at rail-road crossing protection application is shown to highlight the proposed approach

Automating Verification of State Machines with Reactive Designs and Isabelle/UTP

State-machine based notations are ubiquitous in the description of component systems, particularly in the robotic domain. To ensure these systems are safe and predictable, formal verification techniques are important, and can be cost-effective if they are both automated and scalable. In this paper, we present a verification approach for a diagrammatic state machine language that utilises theorem proving and a denotational semantics based on Unifying Theories of Programming (UTP). We provide the necessary theory to underpin state machines (including induction theorems for iterative processes), mechanise an action language for states and transitions, and use these to formalise the semantics. We then describe the verification approach, which supports infinite state systems, and exemplify it with a fully automated deadlock-freedom check. The work has been mechanised in our proof tool, Isabelle/UTP, and so also illustrates the use of UTP to build practical verification tools.Comment: 18 pages, 16th Intl. Conf. on Formal Aspects of Component Software (FACS 2018), October 2018, Pohang, South Kore

A Compositional Framework for Preference-Aware Agents

A formal description of a Cyber-Physical system should include a rigorous specification of the computational and physical components involved, as well as their interaction. Such a description, thus, lends itself to a compositional model where every module in the model specifies the behavior of a (computational or physical) component or the interaction between different components. We propose a framework based on Soft Constraint Automata that facilitates the component-wise description of such systems and includes the tools necessary to compose subsystems in a meaningful way, to yield a description of the entire system. Most importantly, Soft Constraint Automata allow the description and composition of components' preferences as well as environmental constraints in a uniform fashion. We illustrate the utility of our framework using a detailed description of a patrolling robot, while highlighting methods of composition as well as possible techniques to employ them.Comment: In Proceedings V2CPS-16, arXiv:1612.0402

Port Protocols for Deadlock-Freedom of Component Systems

In component-based development, approaches for property verification exist that avoid building the global system behavior of the component model. Typically, these approaches rely on the analysis of the local behavior of fixed sized subsystems of components. In our approach, we want to avoid not only the analysis of the global behavior but also of the local behaviors of the components. Instead, we consider very small parts of the local behaviors called port protocols that suffice to verify properties.Comment: In Proceedings ICE 2010, arXiv:1010.530