  The most recent H1 and ZEUS data for diffractive structure functions are
analyzed under three different theoretical approaches. This includes the
Pomeron Structure Function (PSF) framework, Bartels-Ellis-Kowalski-Wusthoff
(BEKW) color dipole approach and the Golec-Biernat-Wusthoff (GBW) saturation
model. The models are shown to successfully fit the set of combined data.
Conceptual differences between the models are discussed and, as an example, the
prediction for the longitudinal diffractive structure function is presented.
