  We present an extension of the standard model to dark sector with an unbroken
local dark $U(1)_X$ symmetry. Including various singlet portal interactions
provided by the standard model Higgs, right-handed neutrinos and kinetic
mixing, we show that the model can address most of phenomenological issues
(inflation, neutrino mass and mixing, baryon number asymmetry, dark matter,
direct/indirect dark matter searches, some scale scale puzzles of the standard
collisionless cold dark matter, vacuum stability of the standard model Higgs
potential, dark radiation) and be regarded as an alternative to the standard
model. The Higgs signal strength is equal to one as in the standard model for
unbroken $U(1)_X$ case with a scalar dark matter, but it could be less than one
independent of decay channels if the dark matter is a dark sector fermion or if
$U(1)_X$ is spontaneously broken, because of a mixing with a new neutral scalar
boson in the models.
