A Secure State of the OSI-Based Distributed System in the Context of Evaluating Cyber Security

A scientific rationale for cyber security measures is to be based on the use of a particular objective function. This objective function has to integrate and meaningfully describe: the dynamic context of a cyber attack in an operating OSI-based distributed system; the interrelation between hardware- and software-related causes leading to inoperability of system components, including those stemming from cyber attacks; unpredictable parameters (place, time, tools) of authorized information access which causes a violation of a security policy. To introduce the above aspects, we propose to bring into use the concept of a secure state of the OSI-based distributed system, as well as its formal indicator, i.e. a probability of a system security state during check time.