  Allocation of spectrum is an important policy issue and decisions taken have
ramifications for future growth of wireless communications and achieving
universal connectivity. In this paper, on a common footing we compare the
social welfare obtained from the allocation of new spectrum under different
alternatives: to licensed providers in monopolistic, oligopolistic and
perfectly competitive settings, and for unlicensed access. For this purpose we
use mathematical models of competition in congestible resources. Initially we
assume that any new bandwidth is available for free, but we also generalize our
results to include investment decisions when prices are charged for bandwidth
acquisition.
