We started experiments with White Rabbit at LNE-SYRTE for time and frequency dissemination to a large number of users over long haul telecommunication networks. We consider in this paper preliminary work performed on fiber spools, and comparing two situations, one link with one optical fiber and two colors, and a second link with two fibers and a single wavelength. We present preliminary results showing time deviation down to 1 ps at 1000 seconds and Allan deviation as low as 10-15 for about 10000 seconds, for both configurations. We discuss the effect of chromatic dispersion on long haul time transfer regarding stability and accuracy. Finally, we outline our plan for future work.