The calculation of the conductance of disordered rings requires a theory that goes beyond the Kubo-Drude formulation. Assuming "mesoscopic" circumstances the analysis of the electro-driven transitions show similarities with a percolation problem in energy space. We argue that the texture and the sparsity of the perturbation matrix dictate the value of the conductance, and study its dependence on the disorder strength, ranging from the ballistic to the Anderson localization regime. An improved sparse random matrix model is introduced to captures the essential ingredients of the problem, and leads to a generalized variable range hopping picture. ‡ Hence there is no issue of quantum recurrences which would arise for a strictly linear or periodic driving. From here on we use units such that = 1. § The terminology of this paper, and in particular our notion of "conductance" are the same as in the theoretical review [4] and in the experimental work [5].