Improving and Extending the Lim/Lee Exponentiation Algorithm

. In [5] Lim and Lee present an algorithm for fast exponentiation in a given group which is optimized for a limited amount of storage. The algorithm uses one precomputation for several computations in order to minimize the average time needed for one exponentiation. This paper generalizes the previous work proposing several improvements and a method for fast precomputation. The basic Lim/Lee algorithm is improved by determining the optimal segmentation of the exponent. Finally, it is shown that the improved Lim/Lee algorithm is faster than the previous one in average case.