  We consider the linear and nonlinear models of generation of the surface
plasmon-polaritons on the boundary of nonmagnetic dielectric medium and
nonmagnetic metal. We have shown how the three-dimensional incident wave is
transformed to the fluxes of surface plasmon-polaritons at the first and second
harmonics of the TM-mode. These "slow" and "fast" fluxes of the surface
plasmon-polaritons are formed at the both harmonics at the weak interaction. We
obtain that the pulses of surface plasmon-polaritons propagate as the bright
and dark solitons at the strong interaction of the first and second harmonics.
