On the Negative Effects of Trend Noise and Its Applications in Side-Channel Cryptanalysis

Most existing noise reduction methods in side-channel cryptanalysis treat all noises as a whole, instead of identifying and dealing with each of them individually. Motivated by this, this paper investigates the feasibility and implications of identifying trend noise from any other noises in side-channel acquisitions and then dealing with it accordingly. We discuss the effectiveness of applying least square method to remove inherent trend noise in side-channel leakages, and also clarify the limited capability of existing noise reduction methods in dealing with trend noise. We performed a series of correlation power analysis attacks against real power traces publicly available in DPA contest v2 from an unprotected FPGA implementation of Advanced encryption standard (AES) encryption. The experimental results firmly confirmed the soundness and validity of our analysis and observations.