  We analyze the temporal behavior of Network Bright Points (NBPs), present in
the solar atmosphere, using a set of data acquired during coordinated
observations between ground-based observatories (mainly at the NSO/Sacramento
Peak) and the Michelson Doppler Interferometer onboard SOHO. We find that, at
any time during the observational sequence, all the NBPs visible in the NaD2
images are co-spatial within 1 arcsec with locations of enhanced magnetic
field. In analogy with the Ca II K line, the NaD2 line center emission can be
used as a proxy for magnetic structures. We also compare the oscillation
properties of NBPs and internetwork areas. At photospheric levels no
differences between the two structures are found in power spectra, but analysis
of phase and coherence spectra suggests the presence of downward propagating
waves in the internetwork. At chromospheric levels some differences are evident
in the power spectrum between NBPs and internetwork. The power spectrum of NBPs
at the Halpha core wavelength shows an important peak at 2.2 mHz (7 minutes),
not present in the internetwork areas. Its coherence spectrum with Halpha wings
shows very low coherence at this frequency, implying that the oscillations at
these chromospheric levels are not directly coupled with those present in lower
layers.
