The Sensor Open System Architecture (SOSA) is a C4ISR-focused technical and economic collaborative effort between the Air Force, Navy, Army, the Department of Defense (DoD), Industry, and other Governmental agencies to develop (and incorporate) technical Open Systems Architecture standards in order to maximize C4ISR sub-system, system, and platform affordability, re-configurability, overall performance, and hardware/software/firmware re-use. The SOSA effort will effectively create an operational and technical framework for the integration of disparate payloads into C4ISR systems; with a focus on the development of a functional decomposition for common multi-purpose backbone architecture for radar, EO/IR, SIGINT, EW, and communications modalities. SOSA addresses hardware, software, and mechanical/electrical interfaces. The functional decomposition will produce a set of re-useable components, interfaces, and sub-systems that engender re-usable capabilities. This, in effect, creates a realistic and affordable ecosystem enabling mission effectiveness through systematic re-use of all available re-composed hardware, software, and electrical/mechanical base components and interfaces.