Galois field computation

摘要

A method and device for computing the multiplicative inverse of element x in Galois field GF(p^2m) is proposed. In particular, when p is a prime number and m is an integer, the inverse may be constructed based on the observation that x^pm₊₁ is en element in sub-field GF(p^m) and the inverse of x^pm+1 can be carried out in the sub-field. The inverse of X may be obtained by multiplying x^-1=(x^pm₊₁)^-1 by x^pm.