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Reconfigurable intelligent surface (RIS) technology can enhance the performance of wireless systems, but an ad-versary can use such technology to deteriorate communication links. This paper explores an RIS-based attack on multi-user wireless systems that require channel reciprocity for time-division duplexing (TDD). We demonstrate that deploying an RIS with a non-diagonal phase shift matrix can compromise channel reciprocity and lead to poor TDD performance. The attack can be achieved without transmission of signal energy, without channel state information (CSI), and without synchronization with the legitimate system, and thus it is difficult to detect and counteract. We provide an extensive set of simulation studies on the impact of such an attack on the achievable sum rate of the legitimate system, and we design a heuristic algorithm for optimizing the attack in cases where some partial knowledge of the CSI is available. Our results demonstrate that this channel reciprocity attack can significantly degrade the performance of the legitimate system.
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Beyond-Diagonal RIS Attacks on Physical Layer Key Generation
While reconfigurable intelligent surface (RIS) technology shows great promise for wireless communication, an adversary using such technology can threaten wireless performance. This paper explores an RIS-based attack on time-division duplex (TDD) based wireless systems that use channel reciprocity for physical layer key generation (PLKG). We demonstrate that deploying a non-reciprocal RIS with a non-symmetric "beyond diagonal" (BD) phase shift matrix can compromise channel reciprocity and thus break key consistency. The attack can be achieved without transmission of signal energy, channel state information (CSI), and synchronization with the legitimate system, and thus it is difficult to detect and counteract. We propose a physically consistent BD-RIS model and verify the impact of its attack on the secret key rate (SKR) of the legitimate system via simulations. Moreover, we provide a heuristic approach for optimizing the BD-RIS configuration to realize a more severe attack in cases where some partial knowledge of the channel state information is available. Our results demonstrate that such channel reciprocity attacks can significantly decrease the SKR of the legitimate system.
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- PAR ID:
- 10598699
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-9318-7
- Page Range / eLocation ID:
- 946 to 950
- Format(s):
- Medium: X
- Location:
- Lucca, Italy
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SPAWC60668.2024.10694006
