Considerations and examples of a modular open systems approach in defense systems

Abstract

This paper provides an overview of modular open systems approach (MOSA) design principles and open business practices in Department of Defense (DoD) programs, as well as selected examples of MOSA implementations by the Military Departments. The National Defense Authorization Act (NDAA) for Fiscal Year (FY) 2017 (Public Law 114-328) Section 805(a) requires DoD to implement MOSA, and an increasing body of evidence indicates MOSA can enable outcomes that merit consideration and advancement. Most DoD programs had already incorporated MOSA to some extent before the NDAA required it, but the formal acknowledgment in law further emphasizes the currency of the approach. MOSA has multiple, similar definitions. For the purposes of this paper, MOSA is defined as a method to design systems with highly cohesive, loosely coupled, and severable modules that DoD can compete separately and acquire from independent vendors. MOSA is an approach rather than a technical or warfighting requirement. The approach allows the Department to flexibly acquire full capabilities and individual components – including systems, subsystems, and software – and create end item systems and services that can respond to changing threats and missions, allow for technology advances, upgrade and sustain when necessary, and maintain appropriate security assurances. Through this paper, the Office of the Deputy Assistant Secretary of Defense for Systems Engineering (ODASD(SE)) discusses considerations for implementing MOSA, provides three examples of specific implementations by the Air Force, Army, and Navy, and discusses the vision for the future of MOSA application in DoD. The information is based on a literature review of published DoD reports and public documents, interviews with DoD Services discussing lessons, the Services’ written responses to the authors’ requests of exemplars, and review and comments from stakeholders across DoD. The authors concluded that the DoD Services and Agencies’ initiatives contribute to the MOSA body of knowledge and practice.