The hopping of ions in the presence of a random distribution of immobile counterions is discussed theoretically. Our model is found to show dynamical properties in qualitative agreement with a remarkable set of experiments on ion-doped network glasses. In particular it allows us to distinguish two intermediate dynamical regimes, one at low frequencies, where it displays a 'Jonscher-type' response and a second one at high frequencies, with the indication of 'constant-loss-type' behaviour. After a brief summary of the main properties of this 'counterion model' we propose a restricted model which focuses on the high-frequency response and confirms that local ionic motions of dipolar character provide a mechanism for nearly constant loss behaviour. Our analysis is based on Monte Carlo simulations and on a dynamical pair-approximation which qualitatively yields the same trends seen in the simulations.