Algebraic Cryptosystems and Side Channel Attacks
by
Rainer Steinwandt
Universität Karlsruhe, Germany
Coauthors: Jens-Matthias Bohli and Benjamin Glas

Depending on the specific application, side channel attacks can be a crucial threat for encryption and signature schemes. Consequently, for established cryptographic proposals much effort has been invested in deriving efficient implementations that offer acceptable cryptographic security against simple and differential power analysis, timing attacks, etc.

Having in mind the goal of using algebraic cryptosystems-e.g., based on finitely presented groups or multivariate polynomials-in "real life" applications, it is natural to ask for their security with regard to side channel attacks. Using a braid group and a multivariate polynomial based signature scheme as example, the talk discusses possibilities and problems of side channel attacks on algebraic cryptosystems: for a multivariate polynomial based scheme, differential power analysis seems to offer a quite powerful attack tool. On the other hand, for a braid group based proposal applying a differential power analysis against a "naive" implementation seems to be less straightforward than one might expect.

Date received: March 29, 2005