Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Ryuichi Harasawa is active.

Publication


Featured researches published by Ryuichi Harasawa.


field programmable logic and applications | 2014

A soft-core processor for finite field arithmetic with a variable word size accelerator

Aiko Iwasaki; Keisuke Dohi; Yuichiro Shibata; Kiyoshi Oguri; Ryuichi Harasawa

This paper presents implementation and evaluation of an accelerator architecture for soft-cores to speed up reduction process for the arithmetic on GF(2m) used in Elliptic Curve Cryptography (ECC) systems. In this architecture, the word size of the accelerator can be customized when the architecture is configured on an FPGA. Focusing on the fact that the number of the reduction processing operations on GF(2m) is affected by the irreducible polynomial and the word size, we propose to employ an unconventional word size for the accelerator depending on a given irreducible polynomial and implement a MIPS-based soft-core processor coupled with a variable-word size accelerator. As a result of evaluation with several polynomials, it was shown that the performance improvement of up to 10.2 times was obtained compared to the 32-bit word size, even taking into account the maximum frequency degradation of 20.4% caused by changing the word size. The advantage of using unconventional word sizes was also shown, suggesting the promise of this approach for low-power ECC systems.


2015 IEEE Symposium in Low-Power and High-Speed Chips (COOL CHIPS XVIII) | 2015

An energy-efficient FPGA-based soft-core processor with a configurable word size ECC arithmetic accelerator

Aiko Iwasaki; Yuichiro Shibata; Kiyoshi Oguri; Ryuichi Harasawa

This paper proposes an FPGA-based soft core processor architecture equipped with a configurable accelerator to speed up GF(2m) arithmetic for elliptic curve cryptography (ECC) systems. Focusing on the fact the number of operations required for GF(2m) arithmetic is influenced by the relationship between the irreducible polynomial and the machine word size, we propose an approach where the word size of the accelerator is tailored to a given irreducible polynomial. The evaluation results reveal that the performance and the energy efficiency of GF(2m) multiplication including reduction can be improved by up to 6.67 times and 5.24 times, respectively.


international conference on arithmetic of finite fields | 2012

Improving the berlekamp algorithm for binomials x n -a

Ryuichi Harasawa; Yutaka Sueyoshi; Aichi Kudo

In this paper, we describe an improvement of the Berlekamp algorithm, a method for factoring univariate polynomials over finite fields, for binomials xn−a over finite fields


Japan Journal of Industrial and Applied Mathematics | 2007

Tate and Ate pairings for y2 =x5−αx in characteristic five

Ryuichi Harasawa; Yutaka Sueyoshi; Aichi Kudo

\mathbb{F}_{q}


IACR Cryptology ePrint Archive | 2009

A remark on the computation of cube roots in finite fields.

Nozomu Nishihara; Ryuichi Harasawa; Yutaka Sueyoshi; Aichi Kudo

. More precisely, we give a deterministic algorithm for solving the equation


IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences | 2013

Root Computation in Finite Fields

Ryuichi Harasawa; Yutaka Sueyoshi; Aichi Kudo

h(x)^{q} \equiv h(x) \ ({\rm mod}\ x^{n} -a)


Far east journal of applied mathematics | 2011

ON THE BREAK INTERVAL SEQUENCES OF EQUITABLE ROUND-ROBIN TOURNAMENTS

Yutaka Sueyoshi; Ryuichi Harasawa; Aichi Kudo

directly without applying the sweeping-out method to the corresponding coefficient matrix. We show that the factorization of binomials using the proposed method is performed in


IACR Cryptology ePrint Archive | 2006

Tate pairing for y 2 =x 5 -αx in Characteristic Five.

Ryuichi Harasawa; Yutaka Sueyoshi; Aichi Kudo

O \, \tilde{}\, (n \log q)


IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences | 2016

A Simple Improvement for Integer Factorizations with Implicit Hints

Ryuichi Harasawa; Heiwa Ryuto; Yutaka Sueyoshi

operations in


IEICE technical report. Speech | 2014

Accelerating finite field arithmetic with a suitable word size

Aiko Iwasaki; Yuichiro Shibata; Kiyoshi Oguri; Ryuichi Harasawa

\mathbb{F}_{q}

Collaboration


Dive into the Ryuichi Harasawa's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge