  We compute precise estimates for dimensions of 3D-encryption techniques of
3D-point clouds which use permutations and rigid body motion, in which
geometric stability is to be guaranteed. Few attempts are made in this
direction. An attempt is established using the notions of dimensional and
spatial stability by Jolfaei et al. (2015), who also proposed a 3D object
encryption algorithm, claiming that it preserves dimensional and spatial
stability. However, as we mathematically prove neither the algorithm, nor the
associated estimates are correct. We introduce more rigorous definitions of the
geometric stability of such 3D data encryption algorithms, followed by
dimensionality measures
