Computing the endomorphism ring of an ordinary elliptic curve over a finite field
نویسندگان
چکیده
We present two algorithms to compute the endomorphism ring of an ordinary elliptic curve E defined over a finite field Fq . Under suitable heuristic assumptions, both have subexponential complexity. We bound the complexity of the first algorithm in terms of log q , while our bound for the second algorithm depends primarily on log |DE |, where DE is the discriminant of the order isomorphic to End(E ). As a byproduct, our method yields a short certificate that may be used to verify that the endomorphism ring is as claimed.
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عنوان ژورنال:
- IACR Cryptology ePrint Archive
دوره 2009 شماره
صفحات -
تاریخ انتشار 2009