The relationship between the Subordinate JFC and the subordinate component commander is:

OPCON (Operational Control)

Explanation:

Operation control is defined as the power to carry out function of command over subordinate forces. These functions of command may include giving direction with authority, task assignment, employing forces, and objective designation, in order to ensure a mission is accomplished. OPCON is usually exercised via the commanders of subordinate organizations, which includes functional or Service component commanders and subordinate JFCs.