Dynamic Time Warp Based Template Analysis

Abstract

Template analysis attacks on cipher chips take the advantage of data dependency of side channel leakages (power consumption, electromagnetic emission) from cryptographic chips. In this attack, side channel information is analyzed with multivariate model. Papers published are all focus on time domain signal, but the requirement of precise timing arrangement is a fatal weakness in this attack, because it will be useless while there are random delays in cipher under attack. However, it is shown that random delays could be eliminated by the dynamic time warp method. In this paper, based on the description of the principle and steps of template analysis, DTW based template analysis against cryptographic chips was proposed. Experiments of template analysis on a microcontroller (AT89C52) implemented DES verified the feasible of the DTW method.