We analyse 1.5 μm spectropolarimetric observations of quiet regions at different positions on the solar surface. Neither the circular and linear polarization signals nor the area and amplitude asymmetries present a clear trend with the position on the Sun. This fact discards a network-like scenario for the internetwork magnetic fields. An isotropically distributed magnetic field would reproduce the observations, whatever its organisation (myriads of low-lying loops, turbulent field, etc.).