On the existence of distortion maps on ordinary elliptic curves
arXiv:math/0603724
Abstract
Distortion maps allow one to solve the Decision Diffie-Hellman problem on subgroups of points on the elliptic curve. In the case of ordinary elliptic curves over finite fields, it is known that in most cases there are no distortion maps. In this article we characterize the existence of distortion maps in the remaining cases.
3 Pages (Updated version corrects an error in the previous version)