The MOSA Mandate: Deconstructing the Strategic Shift to Modular Open Systems Approach
- Jordan Clayton
- Dec 8, 2025
- 5 min read
For the past five decades, the defense market has functioned as a "black box" ecosystem. This operational model was predicated on proprietary lock-in. When the Navy procured a Arleigh Burke-class destroyer or the Air Force acquired a fighter jet, they were not merely buying a platform; they were purchasing a thirty-year dependency on a single Prime contractor’s proprietary architecture.
In this legacy model, radar systems, weapons control, and mission software were custom-fused into a monolithic entity. The source code was closed. The interfaces were non-standard. A requirement to upgrade a single sensor could trigger a billion-dollar service-life extension program, effectively holding the government hostage to the original equipment manufacturer (OEM).
This vendor lock, once accepted as the cost of doing business, has metastasized into a national security liability. In an era defined by the speed of relevance-where software updates must happen in hours, not years—the Department of Defense (DoD) has shattered the black box.
The solution is the Modular Open Systems Approach (MOSA).
For the commercial executive, it is critical to understand that MOSA is not a suggestion or a guideline. It is a legal mandate codified in Title 10 U.S.C. 2446b. It represents the DoD’s deliberate, statutory strategy to construct an "App Store for War," fundamentally rewriting the rules of acquisition. For technology firms, this is the invitation to compete at the module level rather than the platform level—a direct challenge to the traditional dominance of the Primes.
The Platform Shift: Defining MOSA
MOSA is a design philosophy that mandates weapon systems be constructed like modular arrays rather than bespoke sculptures. It rejects the "monolithic" architecture of the past in favor of a decomposed system.
It relies on five core operational principles:
Modular Design: The decomposition of complex systems into distinct, self-contained units (modules) that perform specific functions.
Open Standards: The utilization of widely supported, non-proprietary interfaces to connect those modules.
Enterprise Investment: A shift toward government-owned "chassis" or backbones, where the government controls the interface.
Transparent Business Practices: The enforcement of fair intellectual property strategies to prevent predatory lock-in.
Rigorous Compliance: The validation of standards through formal conformance testing.
The "iPhone Model" of Warfare: The most effective analogy for this shift is the smartphone. In the legacy model, the DoD bought custom-built phones that ran a single, hard-coded application. If they wanted a new app, they had to buy a new phone.
Under the MOSA regime, the DoD is building common "chassis" (the aircraft, the ship, the ground vehicle) with standardized slots. Firms are no longer required to build the entire phone; they must simply build the best app (the Mission Module) that fits the slot. This lowers the barrier to entry from billions of dollars to millions.
The Strategic Drivers: Why the Black Box is Breaking
The mandate for MOSA is not driven by altruism; it is driven by three operational necessities that the Pentagon can no longer ignore.
1. Speed (The "Afternoon Upgrade")
The Old Way: A new peer-adversary threat emerges in the electromagnetic spectrum. Upgrading a jet's Electronic Warfare (EW) system to counter it requires a 5-year contract to redesign the avionics bay, rewrite the source code, and re-certify the airframe.
The MOSA Way: The Program Executive Office (PEO) issues a solicitation for a "SOSA-aligned 3U EW card." A specialized firm wins the contract, ships the card, and it is plugged into the existing chassis in an afternoon. The platform remains the same; the lethality changes instantly.
2. Competition (Market Fluidity)
The Old Way: Only the original Prime contractor could upgrade the black box, because only they owned the technical data package. This created a de facto monopoly for the lifecycle of the program.
The MOSA Way: The government owns the interface. They can procure the chassis from Lockheed Martin, the radar form factor from Northrop Grumman, and the AI/ML processing module from a Series B startup. This forces constant competition at the component level, driving down cost and driving up performance.
3. Innovation (Lowering Barriers)
The Old Way: Only multi-billion dollar giants with the capacity to integrate massive systems could compete for Programs of Record.
The MOSA Way: Highly specialized firms can plug "Mission Modules" directly into major platforms without needing to integrate the entire ship or aircraft. A founder with a world-class sensor no longer needs to be a sub-contractor to a Prime; they can be a direct provider of a module.
The Rosetta Stone: Speaking the Language of Standards
MOSA is the philosophy; standards are the rulebook. In this environment, alignment is binary. You are either compliant, or you are irrelevant.
SOSA (Sensor Open Systems Architecture): This is the dominant standard for C5ISR (Command, Control, Computers, Communications, Cyber, Intelligence, Surveillance, and Reconnaissance) and Electronic Warfare. If a firm builds high-speed data cards, sensors, or compute modules, they must be SOSA-aligned. It defines the pin-outs, the cooling profiles, and the form factors.
CMOSS (C5ISR/EW Modular Open Suite of Standards): This is the U.S. Army’s specific implementation of SOSA. It is mandatory for next-generation ground vehicles like the OMFV (Optionally Manned Fighting Vehicle). It converges disparate boxes (radio, EW, GPS) into a single chassis with swappable cards.
OMS (Open Mission Systems): This is the U.S. Air Force standard for avionics and subsystem integration. It focuses on the software message bus—how the modules talk to each other.
The Founder’s Playbook: Winning in a Modular World
For the defense tech executive, the capture strategy must pivot from selling a "System" to selling a "Module."
1. Abandon the "Black Box": Pitches based on end-to-end proprietary systems are dead on arrival. If your solution requires the government to adopt a non-standard form factor or a closed data architecture, it represents the enemy of the MOSA model. You will be disqualified during market research.
2. Define the Mission Module The new value proposition is: "We deliver best-in-class capability as a MOSA-compliant, SOSA-aligned 3U module." This signals low integration risk. It tells the PEO that your technology is a "drop-in" upgrade that respects their architecture. It shifts the risk discussion from "integration nightmare" to "future-proof capability."
3. Master the IP Strategy (Open Interface, Closed Core): The most common fear among venture-backed founders is that "Open Systems" means "Open Source," leading to a loss of Intellectual Property. This is false. MOSA mandates an Open Interface, not an open core.
The Interface (Open): The APIs, data formats, physical connectors, and power profiles are built on common standards that everyone can see.
The Core (Closed): The proprietary algorithms, the neural networks, and the trade secrets inside the module remain protected IP. This "black box at the module level" allows firms to protect their secret sauce while remaining compliant with the government's bus architecture.
The Strategic Horizon
The Department of Defense has fundamentally shifted its architectural strategy. It is building the chassis and relying on the private sector to build the modules. Firms that ignore MOSA are building for an obsolete market. Firms that align with it are positioning themselves to be the interchangeable engines of the future force.
The transition to MOSA is not just an engineering challenge; it is a business model transformation. At DualSight, we provide the Strategic Advisory to translate proprietary technology into MOSA-aligned modules and the Capture Strategy to align with the specific PEOs driving this architectural shift. We help you fit the slot that forces adoption.
