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As part of Industrial Control Systems (ICS), the control logic controls the physical processes of critical infrastructures such as power plants and water and gas distribution. The Programmable Logic Controller (PLC) commonly manages these processes through actuators based on information received from sensor readings. Therefore, boundary checking is essential in ICS because sensor readings and actuator values must be within the safe range to ensure safe and secure ICS operation. In this paper, we propose an ontology-based approach to provide the knowledge required to verify the boundaries of ICS components with respect to their safety and security specifications. For the proof of concept, the formal model of the Programmable Logic Controller (PLC) is created in UPPAAL and validated in UPPAAL-API. Then, the proposed boundary verification algorithm is used to import the required information from the safety/security ontology
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An Ontology-Based Framework for Formal Verification of Safety and Security Properties of Control Logics
Any safety issues or cyber attacks on an Industrial Control Systems (ICS) may have catastrophic consequences on human lives and the environment. Hence, it is imperative to have resilient tools and mechanisms to protect ICS. To verify the safety and security of the control logic, complete and consistent specifications should be defined to guide the testing process. Second, it is vital to ensure that those requirements are met by the program control algorithm. In this paper, we proposed an approach to formally define the system specifications, safety, and security requirements to build an ontology that is used further to verify the control logic of the PLC software. The use of ontology allowed us to reason about semantic concepts, check the consistency of concepts, and extract specifications by inference. For the proof of concept, we studied part of an industrial chemical process to implement the proposed approach. The experimental results in this work showed that the proposed approach detects inconsistencies in the formally defined requirements and is capable of verifying the correctness and completeness of the control logic. The tools and algorithms designed and developed as part of this work will help technicians and engineers create safer and more secure control logic for ICS processes.
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- Award ID(s):
- 1846493
- PAR ID:
- 10407355
- Date Published:
- Journal Name:
- 2022 14th International Conference on Electronics, Computers and Artificial Intelligence (ECAI)
- Page Range / eLocation ID:
- 1 to 8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ECAI54874.2022.9847508
