Karpenko A. Methods and tools of ensuring cyber security of globally dis-tributed replicated data storage systems with controlled consistency

The thesis is devoted to ensuring the cyber security of globally distributed repli-cated data storage systems and increasing their resistance to threats of availability and consistency in the conditions of the existing contradiction between these properties due to the use of appropriate methods and means. The object of research is the processes of building and ensuring the security of globally distributed data storage systems under conditions of cyber threats. A complex of new and improved models for globally distributed data storage systems has been developed, which provide: 1) detailing of threats to the cyber security of globally distributed replicated data storage systems; 2) formalization of the descrip-tion of the deployment patterns of the globally distributed replicated data storage sys-tems in the cloud environment, taking into account the domains of readiness using the apparatus of the theoretical-multiple representation; 3) assessment of readiness and re-duction of service time in the conditions of cyber attacks due to the use of the mecha-nism of redundant readings with the help of a hybrid simulation approach. For the first time, a method of dynamic control of the consistency level of glob-ally distributed replicated data storage systems was proposed, which, unlike the known ones, is based on the construction of mixed workload domains and allows to increase the system readiness, while guaranteeing strict data consistency to increase resistance to DDoS attacks. The method of redundant reads of globally distributed replicated data storage systems has been improved, which is based on the use of redundancy with respect to the set level of consistency of read operations and allows to reduce extreme time delays and increase readiness with the set limit on service time or integrity in the conditions of cyber threats of data breaches and denials of service.