Success Thresholds for Power Analysis Attacks Across Multiple Data Encryption Standard (DES) Implementations on a Microcontroller

Using a statistical measure of success which we define as a success threshold, we compare the effectiveness of different types and configurations of side channel power analysis attacks on various implementations of the data encryption standard (DES) cipher realized in a common microcontroller target. Cipher implementations we effect consist of optimized firmware leveraging dedicated cryptographic CPU instructions, portable firmware using generic CPU instructions, and firmware utilizing onboard flash memory to intentionally exaggerate power signatures. Power analysis attacks we employ consist of correlation power analysis (CPA) and differential power analysis (DPA), using both Hamming weight-based and Hamming distance-based power models. As illustrated by the applicable success thresholds, we confirm that non-optimized, generic DES implementations are comparatively significantly easier to defeat than optimized implementations using side channel power analysis techniques.