Model-Based Passive Testing of Safety-Critical Components

Section 5, as well as several Figures and a number of Acknowledgments, which will appear in the above-mentioned book, are not shown in this pre-print paper. Motivation and Overview of this Chapter. Passive testing is a complementary technique to active testing. Under the term 'active testing' we know the 'classical' forms of testing whereby a newly developed system is scrutinized and evaluated before its final installation and deployment. For some types of systems, for example dynamic or adaptive distributed systems which are able to re-configure themselves at runtime in response to changes in their environments, exhaustive active testing before deployment is either theoretically impossible or practically not feasible. For such types of systems the additional application of the technique of passive testing is recommendable, whereby the system is observed at runtime (after deployment) and the correctness of its operations is assessed on the basis of traces (messages, reports) which the passively tested system continues to emit during its operations. Similar to active testing, also passive testing can be planned and designed in a model-based fashion, which is the topic of this chapter. However, a comprehensive theory and taxonomy of methods and techniques for model-based passive testing does –as far as we know– not yet exist and is from today's perspective still very much a topic for future research in this domain. For this reason the presentation of the topic in this chapter is very much example-based such as to provide the reader with some 'first intuitions' about what model-based passive testing is, what kinds of techniques could be used to implement it, and what could be some typical application scenarios for model-based passive testing in the domains of software systems, hardware systems, as ii well as embedded software+hardware systems. On these premises, this chapter is structured and organised as follows: • Section 1 introduces the general principles of model-based passive testing. • Section 2 discusses model-based passive testing in the domain of software systems and provides examples of applicable techniques for the implementation of passive testing in this domain. • Section 3 discusses the relevance of model-based passive testing techniques for another increasingly important application domain, namely the domain of network security. • Section 4 discusses the topic of hardware systems and the relevance of model-based passive testing for this domain, • Section 5 (which is not shown in this pre-print paper) presents stepwise, especially from an educational perspective for …