The weapons systems world is changing. The technology is improving rapidly, requirements for performance are increasing and weapons systems are often required to have 30-50 year service lifetimes. The DoD believes an open systems approach can help. An open system approach considers how a system will be supported throughout its lifecycle at the beginning of the project by using commercially available, widely used interface standards and a modular design approach to combine commercial products from multiple vendors to create a complete weapons system. For the DoD, the recommended method for implementing open systems is MOSA (Modular Open Systems Approach).
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