We provide the first explicit construction of genus 2 curves over finite fields whose Jacobians are ordinary, have large prime-order subgroups, and have small embedding degree. Our algorithm is modeled on the Cocks-Pinch method for constructing pairing-friendly elliptic curves [5], and works for arbitrary embedding degrees k and prime subgroup orders r. The resulting abelian surfaces are define...

Prime field arithmetic plays a central role in computer algebra and supports computation in Galois fields which are essential to coding theory and cryptography algorithms. The prime fields that are used in computer algebra systems, in particular in the implementation of modular methods, are often of small characteristic, that is, based on prime numbers that fit on a machine word. Increasing pre...

Article history: Received 30 March 2011 Accepted 18 February 2013 Available online 15 March 2013

For counting points of jacobians of genus 2 curves over a large prime field, the best known approach is essentially an extension of Schoof’s genus 1 algorithm. We propose various practical improvements to this method and illustrate them with a large scale computation: we counted hundreds of curves, until one was found that is suitable for cryptographic use, with a state-ofthe-art security level...

Let K be a cyclic number field of prime degree `. Heilbronn showed that for a given ` there are only finitely many such fields that are normEuclidean. In the case of ` = 2 all such norm-Euclidean fields have been identified, but for ` 6= 2, little else is known. We give the first upper bounds on the discriminants of such fields when ` > 2. Our methods lead to a simple algorithm which allows one...

In this paper we construct Galois towers with good asymptotic properties over any nonprime finite field F`; i.e., we construct sequences of function fields N = (N1 ⊂ N2 ⊂ · · · ) over F` of increasing genus, such that all the extensions Ni/N1 are Galois extensions and the number of rational places of these function fields grows linearly with the genus. The limits of the towers satisfy the same ...

In this paper we propose a multiplicative blinding scheme for protecting implementations of a scalar multiplication over elliptic curves. Specifically, this blinding method applies to elliptic curves in the short Weierstraß form over large prime fields. The described countermeasure is shown to be a generalization of the use of random curve isomorphisms to prevent side-channel analysis, and our ...

Elementary proofs of the abstract prime number theorem of the form A(w) = qm + 0(qmm~i) for algebraic function fields are given. The proofs use a refinement of a tauberian theorem of Bombieri. 0. Introduction The main purpose of this paper is to give elementary proofs of the abstract prime number theorem for algebraic function fields (henceforth, the P.N.T.) which was established in the author'...

ROBERT C. RHOADES Abstra t. We show that the prime divisors of a random polynomial in Fq[t] are typi ally Poisson Distributed . This result is analogous to the result in Z of Granville [1℄. Along the way, we use a sieve developed by Granville and Soundararajan [2℄ to give a simple proof of the Erdös-Ka theorem in the fun tion eld setting. This approa h gives stronger results about the moments o...

The origin of this work was the search for a “Descartes’ rule” for finite fields a nontrivial upper bound for the number of roots of sparse polynomials. In [2], Bi, Cheng, and Rojas establish such an upper bound. Then, in [3], Cheng, Gao, Rojas, and Wan show that the bound is essentially optimal in an infinite number of cases by constructing t-nomials with many roots in Fpt . However, the bound...