A simplified theoretical model of the structure and dynamics of polymer networks is successfully applied to the transversal 1 H- and 2 H-NMR relaxation in 1,4-cis-polybutadiene networks produced by cross-linking a mix of conventional and partially deuterated chains with thiuram. For both independent relaxation methods the relaxation curves are qualitatively equal and their analysis provides a consistent picture of the characteristic network parameters. Especially the M c values, which were determined by both relaxation methods, are in good agreement with one another and with values obtained from stress-strain measurements