  Coherent transport promises to be the basis for an emerging new technology.
Notwithstanding, a mechanistic understanding of the fundamental principles
behind optimal scattering media is still missing. Here, complex network
analysis is applied for the characterization of geometries that result in
optimal coherent transport. The approach is tailored towards the elucidation of
the subtle relationship between transport and geometry. Investigating systems
with a different number of elementary units allows us to identify classes of
structures which are common to all system sizes and which possess distinct
robustness features. In particular, we find that small groups of two or three
sites closely packed together that do not carry excitation at any time are
fundamental to realize efficient and robust excitation transport. Features
identified in small systems recur also in larger systems, what suggests that
such strategy can efficiently be used to construct close-to-optimal transport
properties irrespective of the system size.
