Two-dimensional "exchange" NMR allows a separate and site specific determination of the two elementary steps in deuteron conduction : deuteron intra-H bond motion and deuteron inter-H bond motion. In Rb-1-x(ND4)(x)D2AsO4 conducting deuteron glasses inter-H bond deuteron transfer is much slower than intra-H bond deuteron transfer. In the above systems the proton intra-H bond exchange is much faster below 100 K than deuteron inter-H bond exchange indicating the importance of phonon assisted tunneling.