North Korea hasn't fired a missile for 60 days, but that may have more to do with its own winter training cycle than with Pyongyang easing off on provocations.

Since Kim Jong Un took power in late 2011, only five of the isolated nation's 85 rocket launches have taken place in the October-December quarter, according to The James Martin Center for Nonproliferation Studies' North Korea Missile Test Database.

The Korean People's Army regularly enters its training cycle every winter "and getting ready for it involves a calm before the storm," said Van Jackson, a strategy fellow at the Center for Strategic Studies at Victoria University of Wellington.