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Although numerous advances have been made during the last two decades in the area of model-based dependability assessment of software systems, many issues are still open. In this chapter, we present a critical discussion of the state of the art based on the approaches presented in Chap. 7 and identify open issue and present some future work directions in the field.

An overview of the techniques traditionally used in dependability analysis that are compliant with current industrial standards (i.e., the International Electrotechnical Commission standards) is provided. In particular, the focus is on those techniques that are chosen as target formalism of model transformations (described in Chap. 7), that is Fault Tree analysis and Petri Net analysis.

This chapter presents a UML profile as an example of mapping the dependability domain model ( Chap. 4) to UML, by using the standard UML extension mechanisms. The DAM profile relies on the standard OMG MARTE profile (Appendix A) and it consists of a set of UML extensions (i.e., stereotypes, tags, and constraints) that enable to annotate a UML model with dependability requirements, input parameters, and metrics for dependability analysis purposes. The chapter explains how to apply DAM extensions in UML-based system models. Two case studies, coming from different application domains, are presented.

This chapter introduces a domain model for the dependability. The model describes core concepts of dependability while provides a vocabulary for it. The domain model bridges the gap between dependability concepts, introduced in Chap. 2, and the dependability profile, described in Chap. 5 The domain model defines information needed to create modeling constructs for dependability-specific modeling languages.

The objective of this chapter is to describe some proposals, of interest for practitioners, from those in Chap. 7 The focus of interest is how these proposals address the translation of a D-DSML into models for analysis. Concretely, the chapter focuses on availability and reliability proposals. We selected one from Bernardi et al., addressing availability and the other from Pai and Dugan, addressing reliability. These two approaches are applied to the case studies developed in Chap. 5 Availability analysis is then applied to the secure distributed system case study, while reliability models are obtained for the mission avionics one.

During the last two decades, several dependability domain-specific modeling languages (D-DSML) have been proposed. This chapter surveys 36 proposals of D-DSML in literature. Most of the proposals are based on UML and a good number also accomplish the transformation of the D-DSML into proper dependability analysis models, as those presented in Chap. 6 DAM, presented in Chap. 5, is an example of D-DSML developed as a UML profile.

This introductory chapter describes the need, importance, and benefits of assessing dependability of software systems. It also establishes the approach followed in the book for dependability assessment.

Maintenance of real-world systems is a complex task involving several actors, procedures and technologies. Proper approaches are needed in order to evaluate the impact of different maintenance policies considering cost/benefit factors. To that aim, maintenance models may be used within availability, performability or safety models, the latter developed using formal languages according to the requirements of international standards. In this paper, a model-driven approach is described for the development of formal maintenance and reliability models for the availability evaluation of repairable systems. The approach facilitates the use of formal models which would be otherwise difficult to manage, and provides the basis for automated models construction. Starting from an extension to maintenance aspects of the MARTE-DAM profile for dependability analysis, an automated process based on model-to-model transformations is described. The process is applied to generate a Repairable Fault Trees model from the MARTE-DAM specification of the Radio Block Centre - a modern railway controller.