  We present the results of three-dimensional numerical simulations to
investigate the excitation of waves in the magnetic network of the Sun due to
footpoint motions of a magnetic flux tube. We consider motions that typically
mimic granular buffeting and vortex flows and implement them as driving motions
at the base of the flux tube. The driving motions generates various MHD modes
within the flux tube and acoustic waves in the ambient medium. The response of
the upper atmosphere to the underlying photospheric motion and the role of the
flux tube in channeling the waves is investigated. We compute the acoustic
energy flux in the various wave modes across different boundary layers defined
by the plasma and magnetic field parameters and examine the observational
implications for chromospheric and coronal heating.
