Hardware Countermeasures against DPA – A Statistical Analysis of Their Effectiveness

Many hardware countermeasures against differential power analysis (DPA) attacks have been developed during the last years. Designers of cryptographic devices using such countermeasures to protect their devices have the challenging task to select and implement a suitable combination of countermeasures. Every device has different requirements, and so there is no universal solution to protect devices against DPA attacks. In this article, a statistical approach is pursued to determine the effect of hardware countermeasures on the number of samples needed in DPA attacks. This approach results in a calculation method that enables designers to assess the resistance of their devices against DPA attacks throughout the design process. This way, different combinations of countermeasures can be easily compared and costly design iterations can be avoided.