  In recent times, impedance side-channel analysis has emerged as a potent
strategy for adversaries seeking to extract sensitive information from
computing systems. It leverages variations in the intrinsic impedance of a
chip's internal structure across different logic states. In this study, we
conduct a comparative analysis between the newly explored impedance side
channel and the well-established power side channel. Through experimental
evaluation, we investigate the efficacy of these two side channels in
extracting the cryptographic key from the Advanced Encryption Standard (AES)
and analyze their performance. Our results indicate that impedance analysis
demonstrates a higher potential for cryptographic key extraction compared to
power side-channel analysis. Moreover, we identify scenarios where power
side-channel analysis does not yield satisfactory results, whereas impedance
analysis proves to be more robust and effective. This work not only underscores
the significance of impedance side-channel analysis in enhancing cryptographic
security but also emphasizes the necessity for a deeper understanding of its
mechanisms and implications.
