Zero collision attack and its countermeasures on Residue Number System multipliers

The Residue Number System (RNS) has been introduced to accelerate the modular multiplications in public-key cryptography. We investigate in this contribution the side-channel leakage of RNS multipliers used in an elliptic curve crypto system. Next to the threat analysis by zero collision attack we investigate different countermeasures to cope with such a physical attack. The resistance against side-channel attacks is improved without great area overhead or loss of speed performance.