Lead PI: Zhiyun Qian 

This thrust addresses the security challenges of an integrated system of systems composed of heterogeneous devices, software platforms, and operating systems, often developed by independent vendors or organizations. Such heterogeneity creates a complex and largely unprecedented attack surface, where interactions across protocol layers and among devices with differing defensive capabilities can introduce unexpected vulnerabilities. To address this, the research will establish a new security paradigm based on layered, mutually reinforcing defenses that work together to provide a stronger and more resilient foundation than any single mechanism could achieve alone.

To realize this vision, the thrust will develop security mechanisms spanning multiple layers of the system. At the physical layer, it will design adaptable approaches grounded in signal processing and information theory to maintain secrecy across diverse devices and operating conditions. At the application layer, it will create decentralized and dynamic access control methods that enable flexible, fine-grained authorization for devices and sensitive operations. The research will also proactively identify vulnerabilities by analyzing heterogeneous systems, protocols, and their cross-layer interactions, with an emphasis on scalable methods for uncovering weaknesses before they can be exploited. In parallel, it will develop complementary defenses to detect malicious behavior from potentially compromised devices through dynamic analysis and customizable runtime detectors tailored to available device resources. These efforts will be closely integrated with machine learning methods developed in the project to strengthen threat detection and adaptive defenses across the heterogeneous network