1. On Methods for the Formal Specification of Fault Tolerant Systems Manuel Mazzara - Newcastle University DEPEND 2011 – The Fourth International Conference on Dependability 24/8/2011 Nice, France [email_address]

3. Overall View Study on Methods (Formal) Methods Definitions HJJ paper (PF + RG + DC) Examples Motivations Tools and Ideas PF Robustness Rely Problem Diagrams Context Diagrams Patterns PQ Fault as interference Ideal FT operations Research Challenges Case Studies RG

4. Our trip

5. A schema for methods evaluation Defining precise steps for the method

7. Applications?

8. Keeping an eye on the real world… “ Man has such a predilection for systems and abstract deductions that he is ready to distort the truth intentionally, he is ready to deny the evidence of his senses only to justify his logic” (Fyodor Dostoyevsky)

11. The method of science* * Rene Descartes: Discourse on Method and Meditations 1. Accept only that which you are sure of 2. Divide each difficulty into small parts 3. Solve problems in an ascending order 4. Assure nothing was omitted

12. We worked on case studies…

17. From the Ideal World to the Real Thinking how to cope with Fault Tolerance

18. The Plato’s Matrix

20. “ There are no facts, only interpretations” (Friedrich Nietzsche)

24. Questions? "Did science promise happiness? I do not believe it. It promised truth, and the question is to know if we will ever make happiness with truth." (Emile Zola)