False-CSI Attacks in Power-Domain NOMA for 6G: A Threat Taxonomy and System-Level Impacts
Cryptography and Security
Summary
The authors explain that power-domain NOMA, a method to share wireless signals more efficiently, relies heavily on accurate information about the communication channel (CSI). They study what happens if this channel information is intentionally faked or biased, which can mess up important processes like sending power signals and ordering users. They create a system to classify these false information attacks and show different types of attacks and how they affect system performance like fairness and security. The authors highlight that false CSI is not just a technical error to fix but a security issue that needs careful attention in future 6G networks.
Authors
Samira Jafarli, Aysha Ebrahim, Suleyman Uludag
Abstract
Power-domain non-orthogonal multiple access (NOMA) remains a widely studied technique for improving spectral efficiency and supporting dense connectivity in beyond-5G and 6G networks. Its main operating mechanisms, however, depend on the integrity of channel-state information (CSI). Power allocation, user ordering, pairing, clustering, and beamforming can all be distorted when the CSI consumed by the base station is deliberately biased rather than merely noisy. This article examines false CSI as an attack surface in power-domain NOMA. We organize the threat space using a compact taxonomy with two primary axes: magnitude, which distinguishes underreporting from overreporting, and ordering effect, which distinguishes order-preserving, boundary, and order-reversing attacks. We then show how coordinated false- CSI behavior, group-changing attacks, direction forgery, pilot spoofing, training-phase injection, and RIS-induced channel manipulation extend this basic taxonomy. Finally, we map each attack family to system-level impacts on power allocation, SIC reliability, scheduler behavior, fairness, throughput, and secrecy. The central message is that false CSI should be treated not only as a channel-estimation problem, but also as a control-input integrity problem for 6G NOMA.