Biblio

In this paper, we tried to summarize the practical experience of information security audits of nuclear power plants' automated process control system (I&C). The article presents a methodology for auditing the information security of instrumentation and control systems for nuclear power plants. The methodology was developed taking into account international and national Russian norms and rules and standards. The audit taxonomy, classification lifecycle are described. The taxonomy of information security audits shows that form, objectives of the I&C information security audit, and procedures can vary widely. A conceptual program is considered and discussed in details. The distinctive feature of the methodology is the mandatory consideration of the impact of information security on nuclear safety.

The new instrumentation and control (I&C) systems of the nuclear power plants (NPPs) improve the ability to operate the plant enhance the safety and performance of the NPP. However, they bring a new type of threat to the NPP's industry-cyber threat. The early fault diagnostic system (EDS) is one of the decision support systems that might be used online during the operation stage. The EDS aim is to prevent the incident/accident evolution by a timely troubleshooting process during any plant operational modes. It means that any significative deviation of plant parameters from normal values is pointed-out to plant operators well before reaching any undesired threshold potentially leading to a prohibited plant state, together with the cause that has generated the deviation. The paper lists the key benefits using the EDS to counter the cyber threat and proposes the framework for cybersecurity assessment using EDS during the operational stage.

As nuclear power plant Instrumentation and Control(I&C) systems have turned into digital systems, the possibility of cyber-attacks has increased. To protect the nuclear power plant from cyber-attacks, digital assets are classified and managed as critical digital assets which have safety, security and emergency preparedness functions. However, critical digital assets represent 70-80% of total digital assets, and applying and managing the same security control is inefficient. Therefore, this paper presents the criteria for identifying digital assets that are classified as vital digital assets that can directly affect the serious accidents of nuclear power plants.

For complex technical objects the research of cybersecurity problems should take into account both physical and information properties of the object. The paper considers a hybrid model that unifies information and physical models and may be used as a tool for countering cyber threats and for cybersecurity risk assessment at the design and operational stage of an object's lifecycle.