No abstract

Metrics are a set of numbers that are used to obtain information about the operation of a process or system. In our case, metrics are used to assess the level of information security of information and communication infrastructure facilities. Metrics in the field of information security are used to quantify the possibility of damage due to unauthorized hacking of an information system, which make it possible to assess the cyber sustainability of the system. The purpose of the paper is to improve information security metrics using multicriteria decision–making methods (MCDM). This is achieved by proposing aggregated information security metrics and evaluating the effectiveness of their application. Classical information security metrics consist of one size or one variable. We obtained the total value by adding at least two different metrics and evaluating the weighting factors that determine their importance. This is what we call aggregated or multicriteria metrics of information security. Consequently, MCDM methods are applied to compile aggregated metrics of information security. These are derived from expert judgement and are proposed for the three management domains of the ISO/IEC 27001 information security standard. The proposed methods for improving cyber sustainability metrics are also relevant to information security metrics. Using AHP, WASPAS and Fuzzy TOPSIS methods to solve the problem, the weights of classical metrics are calculated and three aggregated metrics are proposed. As a result, to confirm the fulfilment of the task of improving information security metrics, a verification experiment is conducted, during which aggregated and classical information security metrics are compared. The experiment shows that the use of aggregated metrics can be a more convenient and faster process and higher intelligibility is also achieved.