CPS: Breakthrough: Analysis, Identification and Mitigation of Delay Performance Bottlenecks of Network Infrastructure in Cyber-Physical Systems

现代社会见证了建立在网络基础设施上的各种分布式网络物理系统(CP)的流行。工业过程控制系统和航空电子设备等关键任务CPS应用的国际标准要求其网络基础设施提供确定性的延迟性能。然而，将CPS理论概念与现实世界的网络性能相结合的问题在很大程度上仍未得到探索。这个项目解决了这个公开的问题，以便对网络挑战空间中的反馈控制CP进行形式化分析。该项目成果可应用于其他涉及实时控制和自适应的CPS应用领域，如车辆控制和通信系统、工业过程控制和片上网络系统。更广泛的影响包括为研究社区开发公开可用的开源软件，并通过提供研讨会和教程以及组织研讨会来教育从高中生和本科生到学术和行业研究人员的广泛受众。该项目的主要目标是建立一种系统的方法来设计、表征和改进CPS中的网络基础设施，作为设计和实施具有时间关键型任务的CPS的突破性结果。与依赖预定义或假定的设备/系统规范的现有研究不同，新方法通过探索基于网络微积分的网络设备和流量来源的测量建模来平衡理论分析和经验评估。该项目还侧重于非前馈网络，而不是最新的针对前馈网络的方法，包括研究基于组合、代数和优化的方法来分析非前馈网络的时延性能，以及识别和缓解联网CP中的时延性能瓶颈。该项目将使用基于PLC(可编程逻辑控制器)的工业自动化系统进行案例研究，不仅展示系统方法的用法和能力，还提供相关算法的参考实现。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Modern societies are witnessing the prevalence of a wide assortment of distributed cyber-physical systems (CPS) built upon network infrastructure. International standards for mission-critical CPS applications, such as industrial process control systems and avionics, require their network infrastructure to provide deterministic delay performance. However, the problem of integrating CPS theoretical concepts with real-world network performance remains largely unexplored. This project addresses this open problem so that feedback control CPS in network-challenged spaces can be analyzed formally. The project result can be applied to many other CPS application domains involving real-time control and adaptation, such as vehicular control and communication systems, industrial process control, and network-on-chip systems. Broader impacts include developing publicly-available open-source software for the research community and educating a wide spectrum of audience, from high-school and undergraduate students to academic and industry researchers, by offering seminars and tutorials and organizing a workshop with strategies to maximize the participation of under-represented groups.The main goal of this project is to establish a systematic approach to the design, characterization, and refinement of network infrastructure in CPS as a breakthrough result for designing and implementing CPS with time-critical tasks. Different from existing studies relying on predefined or presumed device/system specifications, the new approach balances theoretical analyses with empirical evaluations by exploring network-calculus-based modeling of networking devices and traffic sources from measurements. This project also focuses on non-feedforward networks, in contrast to state-of-the-art methods targeting feedforward networks, and includes investigation of compositional, algebraic, and optimization-based approaches to delay performance analysis of non-feedforward networks and research on identification and mitigation of delay performance bottlenecks in networked CPS. This project will use PLC (Programmable Logic Controller)-based industrial automation systems for case studies, not only demonstrating the usage and capabilities of the systematic approach but also providing reference implementation of related algorithms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.