We describe an algorithm for point multiplication on generic ellip-tic curves, based on a representation of the scalar as a sum of mixed powers of 2 and 3. The sparseness of this so-called double-base number system, combined with some efficient point tripling formulae, lead to efficient point multiplication algorithms for curves defined over both prime and… (More)
Searching for similarities in large musical databases has become a common procedure. Local alignment methods, based on dynamic programming, explore all the possible matchings between two musical pieces; and as a result return the optimal local alignment. Unfortunately these very powerful methods have a very high computational cost. The exponential growth of… (More)
—We present the first implementation of RSA in the Residue Number System (RNS) which does not require any conversion, either from radix to RNS beforehand or RNS to radix afterward. Our solution is based on an optimized RNS version of Montgomery multiplication. Thanks to the RNS, the proposed algorithms are highly parallelizable and seem then well suited to… (More)
ÐThe aim of this paper is to accelerate division, square root, and square root reciprocal computations when the Goldschmidt method is used on a pipelined multiplier. This is done by replacing the last iteration by the addition of a correcting term that can be looked up during the early iterations. We describe several variants of the Goldschmidt algorithm,… (More)
In SAC 2003, J. Chung and A. Hasan introduced a new class of specific moduli for cryptography, called the more generalized Mersenne numbers, in reference to J. Solinas' generalized Mersenne numbers proposed in 1999. This paper pursues the quest. The main idea is a new representation, called Modular Number System (MNS), which allows efficient implementation… (More)
A recently introduced double-base number representation has proved to be successful in improving the performance of several algorithms in cryptography and digital signal processing. The index-calculus version of this number system can be regarded as a two-dimensional extension of the classical logarithmic number system. This paper builds on previous special… (More)
In this paper, we propose a efficient and secure point multiplication algorithm, based on double-base chains. This is achieved by taking advantage of the sparseness and the ternary nature of the so-called double-base number system (DBNS). The speed-ups are the results of fewer point additions and improved formulae for point triplings and quadruplings in… (More)
We investigate the impact of larger digit sets on the length of Double-Base Number system (DBNS) expansions. We present a new representation system called extended DBNS whose expansions can be extremely sparse. When compared with double-base chains, the average length of extended DBNS expansions of integers of size in the range 200– 500 bits is… (More)
In this paper we show how the usage of Residue Number Systems (RNS) can easily be turned into a natural defense against many side-channel attacks (SCA). We introduce a Leak Resistant Arithmetic (LRA), and present its capacities to defeat timing, power (SPA, DPA) and electromagnetic (EMA) attacks.
We propose the first general multiplication algorithm in GF (2 k) with a subquadratic area complexity of O(k 8/5) = O(k 1.6). We represent the elements of GF (2 k) according to 2n pairwise prime trinomials, T algorithm is based on Montgomery's multiplication applied to the ring formed by the direct product of the n first trinomials.