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arXiv · 1110.4801

Improvement Of Barreto-Voloch Algorithm For Computing $r$th Roots Over Finite Fields

Zhengjun Cao·Xiao Fan
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Abstract

Root extraction is a classical problem in computers algebra. It plays an essential role in cryptosystems based on elliptic curves. In 2006, Barreto and Voloch proposed an algorithm to compute $r$th roots in ${F}_{q^m} $ for certain choices of $m$ and $q$. If $r\,||\,q-1$ and $ (m, r)=1, $ they proved that the complexity of their method is $\widetilde{\mathcal {O}}(r(\log m+\log\log q)m\log q) $. In this paper, we extend the Barreto-Voloch algorithm to the general case that $r\,||\,q^m-1$, without the restrictions $r\,||\,q-1$ and $(m, r)=1 $. We also specify the conditions that the Barreto-Voloch algorithm can be preferably applied.

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Zhengjun Cao, Xiao Fan. 2011-10-19. Improvement Of Barreto-Voloch Algorithm For Computing $r$th Roots Over Finite Fields. https://arxiv.org/abs/1110.4801

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