Dummy Rounds as a DPA Countermeasure in Hardware

This paper describes the technique of Dummy Rounds as a countermeasure against DPA in hardware implementation of round-based ciphers. Its principle is inspired by several well-known countermeasures used in hardware as Hiding and Dynamic Reconfiguration as well as countermeasures used in software implementations as Dummy cycles, Random order execution or Hiding in time. Being inspired by countermeasures based on dynamic reconfiguration, this method combines hiding of power consumption with hiding in time. In this work we also discuss the amount of randomness available for the control of the computation.