As part of PM PNT, PdM PNT Modernization utilizes a Modular Open Systems Approach (MOSA), formerly known as Open Systems Architecture or Open Systems Approach, to support the DoD strategy for implementation of open systems, in accordance with Title 10 U.S.C. 2446a.(b), Sec 805, which states all major defense acquisition programs (MDAP) are to be designed and developed using a MOSA that: