The Missile Defense Agency (MDA), Department of Defense (DoD), is under the direction, authority and control of the Under Secretary of Defense for Research and Engineering. The mission of the MDA is to develop, test, deploy and sustain a layered Missile Defense System to defend the United States, it deployed forces, allies and friends from missile attacks in all phases of flight. The Missile Defense System is an enduring operationally effective and supportable defensive system of systems against Ballistic Missiles, Hypersonic Missiles, Cruise Missiles (Homeland) and Integrated Air and Missile Defense. The integrated Missile Defense System include; Sea, Land, Space and other cyber domains.