If $\mathbb{F}_q$ is a finite field and the elliptic curve E is defined over finite field $\mathbb{F}_p$ such that ECDLP is hard in E($\mathbb{F}_p$), where $q, p$ are prime and $q \ll p$. Let T $\in E(\mathbb{F}_p)$ with $mT= \mathcal{O}$. My question is in finite field $\mathbb{F}_q, 1=q+1$. It follows that $T=(q+1)T$. Does it imply $q$ have to be divided by $m$? Is it possible that $q$ isn't divided by $m$ with other condition while $1=q+1, T=(q+1)T$? Thank you~

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anomalous. Pick your any elliptic curves and do some computations and you will see your error. (This should be closed.) – Chris Wuthrich Dec 30 '10 at 10:29