17 Dec
2003
17 Dec
'03
11:17 p.m.
I don't know enough about number theory to judge for myself; but you can read the (long) paper yourself at
ftp://netlib.att.com/netlib/att/math/odlyzko/discrete.logs.ps.Z
Thanks for the reference. The paper gives a running time of exp(c(n log n)^(1/2)) for discrete log in GF(p) and exp(c*n^(1/3)*(log n)^(2/3)) for discrete log in GF(2^n). However, this paper was published in 1985. There is now an algorithm to calculate discrete logs in GF(p) in exp(c*n^(1/3)*(log n)^(2/3)) (see prime.discrete.logs.ps.Z in the same directory), so perhaps GF(2^n) isn't so bad after all. Wei Dai