  In this paper, we study theoretically the behavior of a pulse as it
propagates through an intracavity fast-light medium. The method of using a
transfer function to determine a pulse after it passes through a cavity is well
known. However, this approach cannot be used to determine the behavior of the
pulse inside the cavity. To circumvent this constraint, we use an approach that
starts by finding a self-consistent solution for a monochromatic field of
infinite spatial and temporal extents, and determine its amplitudes before,
inside, and after the cavity. We then construct a Gaussian input pulse by
adding a set of these waves, properly phased and weighted, to represent a
moving pulse before the cavity. Adding these waves at various time intervals
then yields the complete spatial profile everywhere, including before, inside
and after the cavity. We first confirm the prediction of this model by
analyzing the behavior of a pulse passing through an empty cavity, and
comparing the prediction of the output with the one produced by the transfer
function method. We then apply the technique to a cavity containing a
fast-light medium. The resulting model allows us to visualize the behavior of
the pulse as it propagates superluminally inside the cavity, and interferes
with itself through multiple bounces. For a vanishing group index, an
interference pattern is formed immediately after the pulse enters the cavity,
with an output pulse emerging with no time delay or distortion. The results
obtained here illustrates the physical mechanism behind pulse propagation
through a white light cavity, a process we have proposed earlier for realizing
a high bandwidth, long delay data buffering system
