  In addition to deep-water rogue waves which develop from the modulation
instability of an optical CW, wave propagation in optical fibers may also
produce shallow water rogue waves. These extreme wave events are generated in
the modulationally stable normal dispersion regime. A suitable phase or
frequency modulation of a CW laser leads to chirp-free and flat-top pulses or
flaticons which exhibit a stable self-similar evolution. Upon collision,
flaticons at different carrier frequencies, which may also occur in wavelength
division multiplexed transmission systems, merge into a single, high-intensity,
temporally and spatially localized rogue pulse.
