"Since discrete exponentiation (calculating xn) is fast (by fast exponentiation, such as binary exponentiation, it takes O(logn)), but no fast way of computing the discrete logarithm a is known, which has many applications in cryptography, such as the Diffie-Hellman protocol."
from: http://en.wikipedia.org/wiki/Finite_field
I am trying to find out why Galois Fields are used in AES. This sentence is not correct English and since I don't know what it is trying to say I am having trouble understanding. Is it saying that computing the value of a Galois Field takes O(logn) but cryptanalyzing it is not? Thanks for any help in advance.
from: http://en.wikipedia.org/wiki/Finite_field
I am trying to find out why Galois Fields are used in AES. This sentence is not correct English and since I don't know what it is trying to say I am having trouble understanding. Is it saying that computing the value of a Galois Field takes O(logn) but cryptanalyzing it is not? Thanks for any help in advance.
