Cyber-Physical Systems (CPSs) engineering profoundly relies on modeling methods to represent the system and study the operation and cybersecurity of CPSs. The operation of a CPS is the result of the collaboration between Information Technology (IT) and Operational Technology (OT) components. While OT focuses on the system’s process physics, the emphasis of IT is on information flow. Consequently, different system models are utilized to study various aspects of CPSs, which may infer different views of the same system. The increasing complexity of CPSs and the high number of cyberattacks against Industrial Control Systems (ICSs) and CPSs in recent years have highlighted the necessity of considering these interrelations based on a unified model to analyze cybersecurity of CPSs. However, the diversity of engineering fields and implicit relations and dependencies between them have made it difficult to integrate the modeling methods towards a unified IT&OT model of CPSs.In this paper, we propose a comprehensive method, based on bond graphs, to model CPS and analyze their cybersecurity. Unlike existing methods, modeling the cyber layer along with the physical layer based on the system flow provides a holistic graphical representation of a CPS, which facilitates collaboration between IT and OT experts.

中文翻译：

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用于信息物理系统网络安全分析的统一 IT&OT 建模


信息物理系统（CPS）工程深深依赖于建模方法来表示系统并研究 CPS 的运行和网络安全。 CPS 的运行是信息技术 (IT) 和运营技术 (OT) 组件之间协作的结果。 OT 侧重于系统的过程物理，而 IT 则侧重于信息流。因此，不同的系统模型被用来研究 CPS 的各个方面，这可能会推断出同一系统的不同视图。近年来，CPS 的复杂性不断增加，以及针对工业控制系统 (ICS) 和 CPS 的大量网络攻击，凸显了基于统一模型考虑这些相互关系来分析 CPS 网络安全的必要性。然而，工程领域的多样性以及它们之间隐含的关系和依赖关系使得很难将建模方法集成到统一的 CPS IT&OT 模型中。在本文中，我们提出了一种基于键合图的综合方法来对 CPS 和分析他们的网络安全。与现有方法不同，基于系统流对网络层和物理层进行建模可提供 CPS 的整体图形表示，从而促进 IT 和 OT 专家之间的协作。