In this paper, we study the computational aspects of calculating the most widely used correlation coefficient: the Pearson product-moment correlation coefficient. We study various time-memory trade-off techniques which apply specifically to the cryptologic setting and present methods to extend already completed computations using incremental versions. Moreover, we show how this technique can be applied to second-order attacks, reducing the attack cost significantly when adding new traces to an existing dataset. We also present methods which allow one to split the potentially huge trace set into smaller, more manageable chunks in order to reduce the memory requirements. Our concurrent implementation of these techniques highlights the benefits of this approach as it allows efficient computations on power measurements consisting of hundreds of gigabytes on a single modern workstation.
Category / Keywords: implementation / Side-channel analysis, CPA, Pearson correlation coefficient, higher-order attacks Date: received 19 Mar 2015, last revised 10 Apr 2015 Contact author: joppe bos at nxp com Available format(s): PDF | BibTeX Citation Version: 20150410:091417 (All versions of this report) Short URL: ia.cr/2015/260 Discussion forum: Show discussion | Start new discussion