The paper discusses the model of fault-tolerant systems Web-services with the removal design faults. Defined set of states Web-service operation for basic models. The process of modeling a fault-tolerant service-oriented Web-system is analyzed, which includes design of macrograph, parameterization (definition of input parameters and their limits), design of oriented graph and systems of differential equations, as well as the study of dependencies on the availability function of input parameters. The results obtained allowed to identify the allowable range of the input parameters: probability of eliminating the identified faultsand maintenance rate to ensure a required level availability function.
Web-service, multifragmental Marcov’s model, availability function