A method to determine the level of the information system fault-tolerance

The study of this article is aimed at determining the level of fault-tolerance of information system components to improve the reliability of the most vulnerable parts. The article proposes a new model for using the Multiple criteria decision making (MCDM) method to solve this problem. It was suggested to use the information system components as alternatives. A set of criteria describes each alternative. Criteria have different units of measurement and different directions of optimization. Normalization is aimed at comparable scales of criteria values. Added coefficients are evaluated using the Additive ratio assessment (ARAS) method. Based on the analysis, the following criteria for assessing the information system fault tolerance are proposed: the failures, the percent of recoverability/maintainability, the percent of the failure effect on the working capacity of information systems, the processed data backup and compliance with legal requirements. The criteria weights were determined using the Analytic Hierarchy Process (AHP) method, based on the expert evaluation.