  We revisit the problem of constraining steps in the inflationary potential
with cosmological data. We argue that a step in the inflationary potential
produces qualitatively similar oscillations in the primordial power spectrum,
independently of the details of the inflationary model. We propose a
phenomenological description of these oscillations and constrain these features
using a selection of cosmological data including the baryonic peak data from
the correlation function of luminous red galaxies in the Sloan Digital Sky
Survey. Our results show that degeneracies of the oscillation with standard
cosmological parameters are virtually non-existent. The inclusion of new data
severely tightens the constraints on the parameter space of oscillation
parameters with respect to older work. This confirms that extensions to the
simplest inflationary models can be successfully constrained using cosmological
data.
