Efficient and secure modular operations using the Adapted Modular Number System

Abstract: The Adapted Modular Number System (AMNS) is a sytem of representation of integers to speed up arithmetic operations modulo a prime p. Such a system can be defined by a tuple (p, n, {\gamma}, {\rho}, E) where E is in Z[X]. In [13] conditions are given to build AMNS with E(X) = {X^n +1}. In this paper, we generalize their results and show how to generate multiple AMNS for a given prime p with E(X)={X^n-\lambda} and {\lambda} in Z. Moreover, we propose a complete set of algorithms without conditional branching to perform arithmetic and conversion operations in the AMNS, using a Montgomery-like method described in [15].