  We study the propagation of discrete solitons on chains of coupled optical
waveguides where finite networks of waveguides are inserted at some points. By
properly selecting the topology of these networks, it is possible to control
the transmission of traveling solitons: we show here that inhomogeneous
waveguide networks may be used as filters for soliton propagation. Our results
provide a first step in the understanding of the interplay/competition between
topology and nonlinearity for soliton dynamics in optical fibers.
