A Simulation-Based Methodology for Evaluating the DPA-Resistance of Cryptographic Functional Units with Application to CMOS and MCML Technologies

This paper explores the resistance of MOS current mode logic (MCML) against differential power analysis (DPA) attacks. Circuits implemented in MCML, in fact, have unique characteristics both in terms of power consumption and the dependency of the power profile from the input signal pattern. Therefore, MCML is suitable to protect cryptographic hardware from DPA and similar side-channel attacks. In order to demonstrate the effectiveness of different logic styles against power analysis attacks, the non-linear bijective function of the Kasumi algorithm (known as substitution box S7) was implemented with CMOS and MCML technology, and a set of attacks was performed using power traces derived from SPICE-level simulations. Although all keys were discovered for CMOS, only very few attacks to MCML were successful.