Webinar shares Modular Open Systems Approach and its associated benefits

By Kate Finkel, Staff Writer

The National Defense Industrial Association (NDIA) conducted the webinar, “ Tech 101: Modular Open Systems Approach (MOSA),” Apr. 23.

MOSA is transforming how defense and aerospace systems are developed, maintained, and upgraded. When executed effectively, MOSA approaches that prioritize modularity and openness can significantly reduce complexity, costs, and development timelines, while promoting innovation and adaptations for future modernizations. Poorly executed MOSA approaches will do the exact opposite.

The webinar, led by Evan Fortunato, president & CEO, Apogee Research, focused on the core principles (modularity and openness) of MOSA-based approaches and their associated benefits, real-world commercial examples to help illustrate these concepts as well as highlighted common challenges encountered in MOSA-based implementations, and addressed the use of standards, discussing where they provide benefits and where they create challenges.

At the beginning of the discussion, Fortunato shared real-world examples to simplify the concepts and make them easier for the audience to understand. When talking about constraints, he explained, “When we think about MOSA as a specific set of constraints, it’s important to understand how those constraints influence the way we build systems. We often think about constraints as ‘good’ or ‘bad,’ as if they are some universal definition.

One example being, houses built with bricks or wood. If you’re trying to stop hurricane force winds, brick makes sense, but most of the U.S. houses are built with wood for good reason because it is more cost effective and maintainable. The key point is that constraints matter on the specific problem you’re trying to solve.”

On the “open” side of MOSA, open refers to the information that is exchanged between the modular components and is known to the people who need to build the modular components. Fortunato explains, “If companies that manufacture coffee filters don’t know the dimensions of the coffee baskets, it gets really hard for them to manufacture the coffee filters.” Open doesn’t have anything to do with publishing information on the open internet. The information can exist within classified systems accessible only to those with the appropriate clearances, or within commercial environments limited to authorized partners.

“Oddly enough,” Fortunato adds, “the open constraint requires that interfaces be clearly known and documented. While this may seem obvious, it’s a recurring problem in DoD systems. They often document the initial design, but when engineers begin building, they discover errors that foreseen by the designers. If those changes aren’t reflected in updated documentation your interfaces are often very different than what has been implemented. In my experience, the vast majority of DoD systems don’t have accurate knowledge of their actual interfaces, and they end up spending significant time reversing the engineering before they can actually start the integrations, which is the underlying root problem here.”