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Digital computing systems have been installed in U.S. Navy ships since the late 1900s. From inception, those computers were viewed as examples of the leading edge of digital technology. They were designed to meet rugged Mil-spec requirements and built on dedicated production lines often in parallel with the best of commercial technology. Mil-spec production offered computers with superior availability and reliability that were able to function effectively in conditions that would have been too adverse for their commercial counterparts. This process produced excellent computing machines for over two decades and allowed Navy combat systems to achieve performance capabilities that were not otherwise attainable.

By the early ’90s the microprocessor was over twenty year old and the desktop workstation had been in service over a decade. The introduction of the personal computer and its use in a large variety of harsh environmental conditions bad pushed the envelope for reliability of commercial products to the point that Mil-spec machines were no longer able to maintain their advantages in performance and reliability. Furthermore, the Navy recognized that the long development cycle required for unique mil-spec products was constraining their ability to rapidly update technology and performance. In order to provide the most capable and affordable processing technology for the Fleet, the Navy needed to adapt its acquisition approach to take advantage of the explosion in commercial technology.

The Navy began this experiment with the introduction of commercial computers housed in rugged racks for the command and control functions in ships. The premise behind these Tactical Computers (the TAC Series) was that they could be competitively procured and re-procured in batch lots from commercial vendors on a schedule to match technology advancement. This strategy was intended to reap the significant cost reductions being experienced in the computing industry. The Navy could then provide these products to their combat system integrators for incorporation into complex weapon systems. These computers would still be custom machines in the sense that the performance required by the
government did not have identical commercial counterparts, however, they would use the same technology, components, and assembly process as the vendor’s commercial products.

Critical to this approach was the ability to procure the next generation TAC computer which could replace its predecessor in a shipboard rack. This required new technology software designs which would allow affordable and reliable transition of applications software to the next generation. In addition, communications between computing assets needed to support new and older generation technologies functioning together. Early efforts to achieve these objectives were impressive and through a maturing of software called the Common Operating Environment (COE) this technique launched a revolution in technology advancement, performance improvements, and cost reductions to the Navy’s command and control functions onboard our ships. The Navy’s TAC program is continuing this approach to executing upgrade cycles for both hardware and software throughout the Navy.

The introduction of Commercial-Off-The-Shelf (COTS) hardware and COE software in shipboard computing has reduced significantly the time required for performance improvements and the cost of upgrades. This has allowed the Navy’s command and control systems to maintain parity with the best available commercial systems. Critical to this goal was to separate the acquisition of the computing asset from the Mil-spec provider and place it squarely into the commercial domain. This evolution was not without controversy. The business interests of Mil-spec providers bad to be re-focused from the manufacture of Mil-spec computers to the integration of COTS systems. It was difficult for some to accept the fact that the commercial computer industry bad displaced the DoD establishment as the definer of the leading edge of hardware and software design, performance, and production. Additionally, many viewed the move to COTS as a reduction in the capabilities of the military systems just to save money. Time and a demonstrated capability to meet mission critical requirements was needed to build confidence and security within the Navy community to allow the role reversal to occur. Now the global marketplace has firmly established itself as the definer of leading edge technology for these computing systems.

Single chip processing power continues to explode with home PCs operating above the 100 MIPS performance point. Complex distributed processing architectures continuing to mature in ways that other combat system functional areas are now following the model established by the introduction of TAC machines. These include the real time processing functions such as fire control and signal processing. A particularly good parallel to the TAC program is emerging in the anti-submarine warfare area. The Multipurpose Processor (MPP) is moving sonar signal processing down the TAC pathway. The MPP was developed under the Small Business Innovation Research (SBIR) program by Digital System Resources, Inc. (DSR) and sponsored jointly by the New Attack Submarine Program (PMO 401) and the Submarine Combat Systems Program (PMS 425). Very much like the TAC, the MPP represents commercial design and construction built to a military performance requirement and housed in a rugged rack. The MPP is designed to address the real time processing requirements of signal and data processing. Once again, critical to the goal of maintaining parity with the revolution in commercial processing technology was the need for a transportable software solution. To address this requirement a software layer called “MPP middleware” was developed which isolates the applications software from the processing hardware. By using this technique the Navy can protect its investments in complex software and competitively reprocure its signal processing assets to gain the cost reductions and performance enhancements being seen in the TAC program and throughout the industry.

Rear Admiral John J. Donegan, Jr. attended the United Stales Naval Academy, and the Naval Postgraduate School at Monterey, California, and graduated in 19’12 with a doctorate in Physics. He joined the AEGIS Shipbuilding Project in 1979 with he led the combat system design team for the Arleigh Buru class destroyer. In 1986 he was assigned to the Strategic Defense Initiative Organization in the Office of the Secretary of Defense. He assumed command of the Naval Research Laboratory, Washington DC in June 1989, and in January 1992 he became the first Commander of the Naval Command, Control and Ocean Surveillance Center. Rear Admiral Donegan retired from the Navy in August, 1994.

Rear Admiral Donegan was recently appointed to the National Research Council of the National Academy of Sciences.

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