Uniformly-switching logic for cryptographic hardware

Recent work on differential power analysis shows that even mathematically-secure cryptographic protocols may be vulnerable at the physical implementation level. By measuring energy consumed by a working digital circuit, one can glean enough information to break encryption. Thwarting such attacks requires a new approach to logic and physical design. In this work, we seek to equalize switching activity of a circuit over all possible inputs and input transitions by adding redundant gates and increasing the overall number of signal transitions. We introduce uniformly-switching (U-S) logic, and present a doubling construction that equalizes power dissipation without requiring drastic changes in CAD tools.