Development of Security Criteria for Complex Systems of Electronic Money Turnover with the Help of Graph Analytics Tools

This paper deals with a graph model for description and investigation of electronic money turnover system. Such approach is based on an idea for consideration of electronic money turnover system as a complex network. The system of money turnover is mapped by a graph with nodes, presenting participants of money turnover (economic agents), and links, reflecting economic relations and remittances between them. The nodes in this model possess different numbers of links, there are some nodes with generous amounts of links, which are considered as hubs (banks, processing centers) in complex network of money turnover. Graph centrality metrics are taken as a foundation of methodology for system analysis, giving an opportunity to create a matrix for classification of stability and security state of a system. An integral criteria metric is suggested, combining a few metrics of graph centrality; values of this metric for all nodes contain information for classification matrix. The distribution of these values allows to classify a system state by stability and security levels as favorable, boundary and unacceptable. A validity of model was investigated by means of crash – tests. These crash-tests procedures include step-by-step consecutive obliteration of randomly chosen central hubs and peripheral graph vertexes and further transaction commitment consideration of in such a “broken” system. Real processes of system destruction owing to both software failure and technical slip-up and cyberattack in systems of electronic money turnover are simulated in such a way. The paper presents dynamics for both centrality metrics of graph and integral metric during graph destruction process and investigate an influence of destruction level on an opportunity of successive transaction, determines the critical metrics values for classification.