Fast exponentiation in subgroups of finite fields
Young-Ho Park, Seyong Jeong, J. Lim · Electronics Letters · 2002
A new method for fast exponentiation is introduced by adapting the work of Gallant, Lambert and Vanstone to finite fields: thus, it is applicable to the multiplicative subgroups of non-prime fields with efficient group homomorphisms such as pth powering maps. When applied to a quartic extension of a 256 bit prime field, the proposed method runs up to 60% faster than ordinary exponentiation in a 1024 bit prime field. (This report is a sequel to a previous report by the authors.)