  Recent radio and optical large scale jets' observations suggest a
two-component jet morphology, consisting of a fast central spine surrounded
with a boundary layer with a velocity shear. We study radiation of electrons
accelerated at such boundary layers as an option for standard approaches
involving internal shocks in jets. The acceleration process in the boundary
layer yields in a natural way a two component electron distribution: a
power-law continuum with a bump at the energy, where energy gains equal
radiation losses, followed by a cut-off. For such distributions we derive the
observed spectra of synchrotron and inverse-Compton radiation, including
comptonization of synchrotron and CMB photons. Under simple assumptions of
energy equipartition between the relativistic particles and the magnetic field,
the relativistic jet velocity at large scales and a turbulent character of the
shear layer, the considered radiation can substantially contribute to the jet
radiative output. In the considered conditions the synchrotron emission is
characterized by a spectral index of the radio-to-optical continuum being
approximately constant along the jet. A characteristic feature of the obtained
broad-band synchrotron spectrum is an excess at X-ray frequencies, similar to
the one observed in some objects by Chandra. As compared to the uniform jet
models, the velocity shear across the radiating boundary region leads to
decrease and frequency dependence of the observed jet-counterjet radio
brightness asymmetry. We conclude that a careful investigation of the
observational data looking for the derived effects can allow to evaluate the
role of the boundary layer acceleration processes and/or impose constraints for
the physical parameters of such layers in large scale jets.
