Welcome!
To use the personalized features of this site, please log in or register.
If you have forgotten your username or password, we can help.
My Menu
Saved Items

An Improved Baby Step Giant Step Algorithm for Point Counting of Hyperelliptic Curves over Finite Fields

Kazuto MatsuoContact Information, Jinhui ChaoContact Information and Shigeo TsujiiContact Information

(5)  Research and Development Initiative, Chuo University, 42-8 Ichigaya Honmuracho, Shinjuku-ku, Tokyo 162-8473, Japan
(6)  Dept. of Electrical, Electronic and Communication Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8851, Japan
(7)  Dept. of Information and System Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8851, Japan
Abstract
Counting the number of points of Jacobian varieties of hyperelliptic curves over finite fields is necessary for construction of hyperelliptic curve cryptosystems. Recently Gaudry and Harley proposed a practical algorithm for point counting of hyperelliptic curves. Their algorithm consists of two parts: firstly to compute the residue modulo an integer m of the order of a given Jacobian variety, and then search for the order by a square-root algorithm. In particular, the parallelized Pollard’s lambda—method was used as the square-root algorithm, which took 50CPU days to compute an order of 127 bits.
This paper shows a new variation of the baby step giant step algorithm to improve the square—root algorithm part in the Gaudry-Harley algorithm. With knowledge of the residue modulo m of the characteristic polynomial of the Frobenius endomorphism of a Jacobian variety, the proposed algorithm provides a speed up by a factor m, instead of √m in square—root algorithms. Moreover, implementation results of the proposed algorithm is presented including a 135-bit prime order computed in 16 hours on Alpha 21264/667MHz.

Contact Information Kazuto Matsuo
Email: mats@m.ieice.org

Contact Information Jinhui Chao
Email: jchao@elect.chuo-u.ac.jp

Contact Information Shigeo Tsujii
Email: tsujii@ise.chuo-u.ac.jp
Fulltext Preview (Small, Large)
Image of the first page of the fulltext

References secured to subscribers.



Export this chapter
Export this chapter as RIS | Text
 
Remote Address: 38.107.191.108 • Server: mpweb01
HTTP User Agent: CCBot/1.0 (+http://www.commoncrawl.org/bot.html)