A verification of the bakery protocol combining algebraic and model-oriented techniques

In this paper we give a specification of the so called Bakery protocol in an extension of the process algebra ACP with abstract datatypes. We prove that this protocol is equal to a Queue, modulo branching bisimulation equivalence. The verification is as follows. First we give a linear specification of the Bakery, that is a specification without parallelism. Then we introduce an invariant and encorporate this invariant into the linear specification of the Bakery and the specification of the Queue. Finally, we give a boolean function on the arguments of the resulting specification of the Bakery and the Queue, and we prove that by its equations it defines a branching bisimulation. This paper can be considered as an alternative to the proof of Groote and Korver [GK94], that proves the correctness of the Bakery protocol modulo weak bisimulation (or observational congruence) completely within the proof system of $mu$CRL

Deriving tolerant grammars from a base-line grammar

A grammar-based approach to tool development in re- and reverse engineering promises precise structure awareness, but it is problematic in two respects. Firstly, it is a considerable up-front investment to obtain a grammar for a relevant language or cocktail of languages. Existing work on grammar recovery addresses this concern to some extent. Secondly, it is often not feasible to insist on a precise grammar, e.g., when different dialects need to be covered. This calls for tolerant grammars. In this paper, we provide a well-engineered approach to the derivation of tolerant grammars, which is based on previous work on error recovery, fuzzy parsing, and island grammars. The technology of this paper has been used in a complex Cobol restructuring project on several millions of lines of code in different Cobol dialects. Our approach is founded on an approximation relation between a tolerant grammar and a base-line grammar which serves as a point of reference. Thereby, we avoid false positives and false negatives when parsing constructs of interest in a tolerant mode. Our approach accomplishes the effective derivation of a tolerant grammar from the syntactical structure that is relevant for a certain re- or reverse engineering tool. To this end, the productions for the constructs of interest are reused from the base-line grammar together with further productions that are needed for completion

Chapter 6: The Compact Dynamic Bus Station

AbstractThis document is one of the parts of the electronic version of the PhD thesis by S.F.M. van Vlijmen [8]. The goal of the PhD project was to get a better understanding of the problems with the integration of formal specification technique in the day to day software practice. The approach followed was to execute a number of projects in cooperation with industry on realistic cases.In this document is reported on the design of an innovative system for the control of bus stations. The innovative aspect is that buses do not have a fixed platform at the station, the platform is dynamically assigned and communicated to the driver upon entering the station. It was tried to specify data and processes in an algebraic style. During the project it turned out that formal specification in this style did not work to our advantage

Industrial applications of ASF+SDF

In recent years, a number of Dutch companies have used the algebraic specification formalism ASF+SDF. Bank MeesPierson has specified a language for describing interest rate products, their translation into COBOL, and their generation from interactive questionnaires. A consultancy company has specified a language to represent the company's object-oriented models, and the compilation of this language into Access. Bank ABN-AMRO has started investigating the use of algebraic specifications for renovating legacy COBOL systems. We discuss the implications of such projects for teaching algebraic specifications and software engineering, and the role students have been playing in these projects

Het huis Spoor- en Veldzicht: een kleine verantwoording

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