Augmenting Bit-Level Network Security Using Physical Layer RF-DNA Fingerprinting

Successful "cracking" of bit-level security compromises network integrity and physical layer augmentation is being investigated to improve overall security. Intra-cellular security is addressed here using device-specific RF "Distinct Native Attribute" (RF-DNA) fingerprints in a localized regional air monitor, with targeted applications including cellular networks such as the Global System for Mobile (GSM) Communications and last mile Worldwide Interoperability for Microwave Access (WiMAX) systems. Previous work demonstrated GSM inter-manufacturer classification (manufacturer discrimination) using RF-DNA fingerprinting and achieved accuracies of 92% at SNR = 6 dB. These results are extended here for intra-manufacturer classification (serial number discrimination). Historically, intra-manufacturer discrimination has posed the greatest challenge and RF-DNA fingerprinting has been effective with both Orthogonal Frequency Division Multiplexed (OFDM) and Direct Sequence Spread Spectrum (DSSS) network signals. Intra-manufacturer GSM results are provided here based on identical signal collection, fingerprint generation, and MDA/ML classification processes used for previous inter manufacturer assessment. When comparing performance, the trend for GSM intra-manufacturer classification is consistent with previous work for other network-based signals and device classification is much more challenging. For classification accuracies of 80% or better, intra manufacturer fingerprinting requires an increase of 20-25 dB in SNR to achieve inter-manufacturer performance.