Education
In 1979 Koval graduated the Kamianets-Podilsky Higher Military-Engineer Command School.
In 1979 Koval graduated the Kamianets-Podilsky Higher Military-Engineer Command School.
During the 2014 Crimea crisis he was appointed as the Minister of Defense replacing Admiral Ihor Tenyukh who resigned. Until 1987 he served in the Soviet Airborne Troops (VDV), after which he entered the Frunze Military Academy in Moscow and graduated it in 1990. In 1990-1995 Koval served in a VDV training center.
In 1997 he also graduated the National University of Defense of Ukraine.
In 1997-1999 Koval worked in commanding positions of the Northern Operation Command, in 1999-2001 - the Western Operation Command. In 2001-2002 he served as the First Deputy Commander of the Internal Troops of Ukraine, since 2002 and until 2013 - the First Deputy Commander of the State Border Guard Service of Ukraine.