  We present theoretical modelling for the very rapid TeV variability of PKS
2155--304 observed recently by the H.E.S.S. experiment. To explain the
light-curve, where at least five flaring events were well observed, we assume
five independent components of a jet that are characterized by slightly
different physical parameters. An additional, significantly larger component is
used to explain the emission of the source at long time scales. This component
dominates the emission in the X-ray range, whereas the other components are
dominant in the TeV range. The model used for our simulation describes
precisely the evolution of the particle energy spectrum inside each component
and takes into account light travel time effects. We show that a relatively
simple synchrotron self-Compton scenario may explain this very rapid
variability. Moreover, we find that absorption of the TeV emission inside the
components due to the pair creation process is negligible.
