Validating an Analytical Approximation through Discrete Simulation

While Markov models have been extensively used to study the availability of replicated data, they cannot handle effectively network configurations where sites failures and network partitions have to be simultaneously considered. We had proposed in a previous paper a hierarchical decomposition method aimed at overcoming this limitation. While our method could provide closed form estimates of the availability of replicated objects whose replicas reside on networks subject to communication failures. We present here a simulation study measuring the quality of our estimates and attempting to improve upon them.