Differential power analysis: Simulated versus experimental attacks

This paper presents differences and similarities between experimental and simulated differential power analysis (DPA) based security attacks. DPA attacks are known for many years and experimental attacks have been performed on a large number of hardware and/or software implementations of various cryptographic algorithms (RSA, AES, etc.). Vulnerabilities are mostly discovered after the product has been released to the market making it quasi impossible to fix them. Therefore, a new approach to detecting security vulnerabilities is needed; one that detects flaws early in the design process, before the circuit is manufactured. This method relies on digital simulations rather than on experimental measurements. Simulations are the foundation of functional verification of digital circuits. Using a specifically for this purpose developed software framework, called Power Analysis Toolkit, a comparison between simulated and experimental DPA attacks was performed. The attacked circuit is a hardware implementation of the well-known AES cryptographic algorithm. Results show that, using the correct assumptions, digital simulations can be used to uncover security vulnerabilities.