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

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 organically integrating CPS theories with network performance analysis remains largely unexplored. This project addresses this open problem so that feedback control CPS in network-challenged spaces can be analytically investigated. 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.