None of us really know the answer because its common practice for Governments too keep a vast percent of those matters confidential.
However,in terms of sophistication were talking the industrial nations like Japan,UK,Germany,France,Canada,U.S,Russia,and so on and on.Addressing the matter of size(extensive),were talking Countries with large populations that often practice inscribing there young men into the Military, and Nations that spend large amounts of GDP on Defence Forces.
