Testbed-Driven Assessment: Experimental Validation of System Security and Reliability
Efforts are underway to switch existing nuclear power plants (NPPs) based on analog control systems to digital control systems. It is expected that digital Instrumentation and Control (I&C) systems will be used in all future NPPs, and they are expected to solve the obsolescence problem of analog components and to improve safety and performance. However, before analog systems can be switched to digital, much work needs to be done to ensure the safety of the new systems to the level required by the nuclear sector. The goal of this research activity was to identify and experimentally evaluate possible faults and attacks against the safety-critical digital I&C systems destined for use in NPPs. In pursuit of that goal, to study and validate the failure and attack behavior of the safety-critical digital I&C systems, this project built a testbed with real-time simulation of an NPP in conjunction with physical digital I&C components for realistic NPP operation simulation. We experimentally evaluated the resiliency and security of the digital I&C system, and identified potential attack vectors, single points of failure, and common mode failures in future digital I&C systems. We developed fault injection and attack simulation tools to simulate various failures and attacks on the testbed, and developed logics to analyze and report on the impact of failures and attacks on the safety-critical digital I&C components of an NPP. The testbed provides the ability to simulate the operation of an NPP with real-time control feedback from the digital controller. Potential future uses of the testbed include cyber security tests of digital I&C systems for NPPs, stability analysis of the NPP testbed connected to a simulator of the electric grid, and human machine interface and human factor engineering studies of newly developed control rooms for NPPs.