Reliability models of complex state control in spatially distributed information security systems

The paper considers distributed systems widely used in practice, which involve the storage and processing of information critical for enterprises and institutions on the periphery, analyzes the range of vulnerabilities in relation to information security (IS) of enterprises, organizations, educational institutions, etc. The article provides a detailed analysis of the application of the mathematical apparatus of the theory of queuing used to study the information security of distributed systems. The goals and objectives were set based on the results of the analysis, which showed that the existing ratio “distributed infocommunication system - IS threats” does not fully reflect the property of reliability of data on the state of IS for the number of elements (sensors) involved in providing IS for this information system and the number of channels through which threats to this information system can come. Thus, the purpose of this work is to develop a mathematical model based on Markov random processes and queuing theory, which allows using probabilistic methods to evaluate the relevance of information about possible threats in the field of information security in dynamics and take preventive measures to eliminate them. Materials and methods. The research is based on the idea that there is some information system that can be exposed to threats in the field of information security, threats can come through some channels. For mathematical modeling of the described situation, a number of restrictions are introduced, taking into account which it is shown that the reliability of data on information threats can be investigated on the basis of Markov random processes. Results. Using the model of reliability of complex monitoring of states in spatially distributed IS systems, the following were obtained: dependences of the probability of reliability of information about threats on the intensity of their arrival with a different number of threat sources; dependence of the probability of reliability of information on the time of receipt and processing of information with a different number of sources of threats; the minimum values of the elements, which are necessary to ensure the reliability of information with a probability not less than a given one, with a known number of threat sources for different values of the intensity of their arrival, and others. Conclusion. The dependences obtained are quasi-linear in nature, which makes it possible to carry out approximate, but sufficiently accurate calculations when evaluating these parameters, which will make it possible to effectively organize information security measures. The developed model will allow for operational planning of an information system protection strategy against possible threats, as well as support for decision-making on the number of information security elements in changing conditions of confronting external information influences.