  We have presented theoretical and numerical studies on interactions of
dispersive waves with second order solitons. Disperive wave with considerable
intensity resonantly colliding with the second order solitons can lead to
acceleration/decceleration of the later with subsequent central frequency
shifts, but still well preserve the oscillating structure of the 2-solitons.
The 2-soliton creates an effective periodical refractive index profile and thus
reflected and transmitted dispersive waves generate new spectral bands with
sharp peak structures. When resonant dispersive waves interact with two second
order solitons bounding them, multiple scattering with multiple frequency
conversion of the radiation occurs. Thus 2-solitons and radiation trapped in
between them can produce effective solitonic cavity with "flat" or "concave
mirrors" depending on the intensity of the input.
