El Akchioui

In this book, we have presented the various components of system dependability, as well as the derivation of various reliability indicators from Markov analysis, whose limitations we have clearly underlined. These performance indicators can be obtained using Markov analysis, but this task requires time to compute the state graph beforehand, and then the difficulty of solving a system of equations to determine the steady-state probabilities. To alleviate this problem of combinatorial explosion in the number of states, in the case of complex systems, stochastic timed Petri nets are introduced.In this work, we have highlighted the limitations due to the combinatorial explosion of the number of states by Markov analysis and to convergence problems by the stochastic estimator.