International conference on Arithmetic of finite fields 

About: International conference on Arithmetic of finite fields is an academic conference. The conference publishes majorly in the area(s): Finite field & Elliptic curve. Over the lifetime, 140 publications have been published by the conference receiving 1891 citations.

On the Classification of 4 Bit S-Boxes

Abstract: In this paper we classify all optimal 4 bit S-boxes. Remarkably, up to affine equivalence, there are only 16 different optimal S-boxes. This observation can be used to efficiently generate optimal S-boxes fulfilling additional criteria. One result is that an S-box which is optimal against differential and linear attacks is always optimal with respect to algebraic attacks as well. We also classify all optimal S-boxes up to the so called CCZ equivalence. We furthermore generated all S-boxes fulfilling the conditions on nonlinearity and uniformity for S-boxes used in the block cipher Serpent. Up to a slightly modified notion of equivalence, there are only 14 different S-boxes. Due to this small number it is not surprising that some of the S-boxes of the Serpent cipher are linear equivalent. Another advantage of our characterization is that it eases the highly non-trivial task of choosing good S-boxes for hardware dedicated ciphers a lot.

New Point Addition Formulae for ECC Applications

Abstract: In this paper we propose a new approach to point scalar multiplication on elliptic curves defined over fields of characteristic greater than 3. It is based on new point addition formulae that suit very well to exponentiation algorithms based on Euclidean addition chains. However finding small chains remains a very difficult problem, so we also develop a specific exponentiation algorithm, based on Zeckendorf representation (i.e. representing the scalar kusing Fibonacci numbers instead of powers of 2), which takes advantage of our formulae.

Towards Optimal Toom-Cook Multiplication for Univariate and Multivariate Polynomials in Characteristic 2 and 0

Abstract: Toom-Cook strategy is a well-known method for building algorithms to efficiently multiply dense univariate polynomials. Efficiency of the algorithm depends on the choice of interpolation points and on the exact sequence of operations for evaluation and interpolation. If carefully tuned, it gives the fastest algorithm for a wide range of inputs. This work smoothly extends the Toom strategy to polynomial rings, with a focus on . Moreover a method is proposed to find the faster Toom multiplication algorithm for any given splitting order. New results found with it, for polynomials in characteristic 2, are presented. A new extension for multivariate polynomials is also introduced; through a new definition of density leading Toom strategy to be efficient.

Some Theorems on Planar Mappings

Abstract: A mapping $f:{\mathbb{F}}_p^n\to {\mathbb{F}}_p^n$ is called planar if for every nonzero $a \in {\mathbb{F}}_p^n$ the difference mapping D f,a : xi¾?f(x+ a) i¾? f(x) is a permutation of ${\mathbb{F}}_p^n$. In this note we prove that two planar functions are CCZ-equivalent exactly when they are EA-equivalent. We give a sharp lower bound on the size of the image set of a planar function. Further we observe that all currently known main examples of planar functions have image sets of that minimal size.

Structure of pseudorandom numbers derived from fermat quotients

Abstract: We study the distribution of s-dimensional points of Fermat quotients modulo p with arbitrary lags. If no lags coincide modulo p the same technique as in [21] works. However, there are some interesting twists in the other case. We prove a discrepancy bound which is unconditional for s = 2 and needs restrictions on the lags for s > 2.We apply this bound to derive results on the pseudorandomness of the binary threshold sequence derived from Fermat quotients in terms of bounds on the well-distribution measure and the correlation measure of order 2, both introduced by Mauduit and Sarkozy. We also prove a lower bound on its linear complexity profile. The proofs are based on bounds on exponential sums and earlier relations between discrepancy and both measures above shown by Mauduit, Niederreiter and Sarkozy. Moreover, we analyze the lattice structure of Fermat quotients modulo p with arbitrary lags.