  Similarly to the larger Galactic ridge, the Galactic center region presents a
hard diffuse emission whose origin has been strongly debated for the past two
decades: does this emission result from the contribution of numerous, yet
unresolved, discrete point sources ? Or does it originate in a truly diffuse,
hot plasma ?
  The Galactic center region (GC) is however different on many respects from
the outer parts of the Galaxy, which makes the diffuse emission issue at the
Galactic center unique. Although recent observations seem to favour a point
sources origin in the far Galactic ridge, the situation is still unclear at the
GC and new observations are required.
  Here we present results on the modeling of the truly diffuse plasma.
Interestingly, such a plasma would strongly affect the dynamics of orbiting
molecular clouds and thus the central engine activity. Discriminating between
the two hypothesis has thus become a crucial issue in the understanding of this
central region that makes the link between the inner small accretion disk and
the large scale Galactic dynamics. We investigate the new inputs we can expect
from Simbol-X on this matter.
