Research of safety and survivability models of the information system for critical use

The article presents the models of safety and survivability of the information system for critical use (ISCU) in the paradigm of Markov models. In the safety model the ISCU studied is represented by a structured set of coupled subsystems, each characterized by the intensity of a dangerous failure and by the intensity of the recovery of a safety. The model allows the estimation of the probability of finding ISCU in each of a set of states that describe the available configurations of failures of the ISCU's subsystems, taking into account the above characteristics. The ISCU's survivability model has also been created to assess the values of the introduced taxonomy of survivorship attributes for an active subject-systemic interaction session during which deterministic failures may occur. Synthesis of the survivability model takes into account the ISCU architecture, access control subsystem functions, system security policy settings, etc.