The Battle of Metasurfaces: Understanding Security in Smart Radio Environments

2025-11-17

AI Summary

In intelligent radio environments where both attackers and defenders deploy reconfigurable intelligent surfaces (RISs), conventional unidirectional RIS-based physical-layer security mechanisms fail, necessitating a fundamental understanding of novel security paradigms under adversarial metasurface interactions. Method: We present the first systematic modeling and experimental validation of context-agnostic RIS adversarial interaction mechanisms, integrating theoretical analysis with real-world Wi-Fi testbed experiments to quantify the impact of time dynamics, spatial positioning, reconfiguration strategies, and hardware scale on the博弈 outcome. Contribution: We demonstrate that adversarial RISs can mutually cancel—or even completely nullify—their channel manipulation effects, thereby invalidating the foundational assumption of unidirectional security. Furthermore, we propose a new physical-layer security design framework tailored for bidirectional RIS games, providing both rigorous theoretical foundations and empirical validation for ultra-reliable wireless systems.

Technology Category

• Game Theory and Economic Paradigms: Adversarial Learning
• Multiagent Systems: Adversarial Agents
• Machine Learning: Adversarial Learning & Robustness

Application Category

• Security and Privacy: Large-scale security measurements
• User Modeling, Personalization and Recommendation: Attacks and countermeasures in recommendation systems
• Responsible Web: Measurement, analysis, and circumvention of Web censorship

Abstract

Metasurfaces, or Reconfigurable Intelligent Surfaces (RISs), have emerged as a transformative technology for next-generation wireless systems, enabling digitally controlled manipulation of electromagnetic wave propagation. By turning the traditionally passive radio environment into a smart, programmable medium, metasurfaces promise advances in communication and sensing. However, metasurfaces also present a new security frontier: both attackers and defenders can exploit them to alter wireless propagation for their own advantage. While prior security research has primarily explored unilateral metasurface applications - empowering either attackers or defenders - this work investigates symmetric scenarios, where both sides possess comparable metasurface capabilities. Using both theoretical modeling and real-world experiments, we analyze how competing metasurfaces interact for diverse objectives, including signal power and sensing perception. Thereby, we present the first systematic study of context-agnostic metasurface-to-metasurface interactions and their implications for wireless security. Our results reveal that the outcome of metasurface "battles" depends on an interplay of timing, placement, algorithmic strategy, and hardware scale. Across multiple case studies in Wi-Fi environments, including wireless jamming, channel obfuscation for sensing and communication, and sensing spoofing, we demonstrate that opposing metasurfaces can substantially or fully negate each other's effects. By undermining previously proposed security and privacy schemes, our findings open new opportunities for designing resilient and high-assurance physical-layer systems in smart radio environments.

Problem

• Analyzes symmetric metasurface interactions between attackers and defenders
• Investigates metasurface battles' impact on wireless security and sensing
• Examines mutual neutralization effects in competing metasurface applications

Innovation

• Symmetric metasurface capabilities for both attackers and defenders
• Context-agnostic metasurface-to-metasurface interaction analysis
• Real-world experiments demonstrating mutual metasurface effect negation