  We determine the scaling exponents of polymer translocation (PT) through a
nanopore by extensive computer simulations of various microscopic models for
chain lengths extending up to N=800 in some cases. We focus on the scaling of
the average PT time $\tau \sim N^{\alpha}$ and the mean-square change of the PT
coordinate $<s^2(t)> \sim t^\beta$. We find $\alpha=1+2\nu$ and
$\beta=2/\alpha$ for unbiased PT in 2D and 3D. The relation $\alpha \beta=2$
holds for driven PT in 2D, with crossover from $\alpha \approx 2\nu$ for short
chains to $\alpha \approx 1+\nu$ for long chains. This crossover is, however,
absent in 3D where $\alpha = 1.42 \pm 0.01$ and $\alpha \beta \approx 2.2$ for
$N \approx 40-800$.
