High Dependability Computing Program Modeling Dependability(3)

Individuals and organizations increasingly use sophisticated software systems from which they demand great reliance. “Reliance ” is contextually subjective and depends on the particular stakeholder’s needs; therefore, in different circumstances, the sta

Table of Contents

1 Introduction...........................................................................................................................4 2 The Unified Model of Dependability (UMD)..................................................................6

2.1 Identifying the building blocks of dependability....................................................6

2.2 “Robustness” of UMD..............................................................................................10

2.3 UMD to capture stakeholders dependability needs..............................................14

2.4 Measuring dependability..........................................................................................16

2.5 Enhancing UMD: capturing the “System Reaction”............................................17

2.6 The UMD Tool..........................................................................................................19 3 Applying UMD to build a System Dependability Model.............................................19

3.1 The case study – TSAFE..........................................................................................19

3.2 Data Gathering...........................................................................................................21

3.3 Data Analysis.............................................................................................................24 4 Formalizing the UMD application process.....................................................................28

4.1 The single-stakeholder scenario..............................................................................28

4.2 The multiple-stakeholder scenario..........................................................................29 5 Conclusions and future work............................................................................................30 6 References...........................................................................................................................31 Appendix A – Description of the UMD Tool.........................................................................33