Of course like other engineering fields the government has escape clauses in

Of course like other engineering fields the

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Of course, like other engineering fields, the government has escape clauses in the contracts that let it still acquire the product even if it is late. Ironically, the contractor makes more money the longer it takes to develop the software. Thus, the art is negotiating the contract and the penalty clauses. As one commentator on ACA noted ( Howard 2013 ), “The firms that typically get contracts are the firms that are good at getting contracts, not typically good at executing on them.” Another noted that the Plan-and-
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Document approach is not well suited to modern practices, especially when government contractors focus on maximizing profits ( Chung 2013 ). An early version of this Plan-and-Document software development process was developed in 1970 ( Royce 1970 ). It follows this sequence of phases: 1. Requirements analysis and specification 2. Architectural design 3. Implementation and Integration 4. Verification 5. Operation and Maintenance Given that the earlier you find an error the cheaper it is to fix, the philosophy of this process is to complete a phase before going on to the next one, thereby removing as many errors as early as possible. Getting the early phases right could also prevent unnecessary work downstream. As this process could take years, the extensive documentation helps to ensure that important information is not lost if a person leaves the project and that new people can get up to speed quickly when they join the project. Because it flows from the top down to completion, this process is called the Waterfall software development process or Waterfall software development lifecycle . Understandably, given the complexity of each stage in the Waterfall lifecycle, product releases are major events toward which engineers worked feverishly and which are accompanied by much fanfare. Windows 95 was heralded by a US$300 million outdoor party for which Microsoft hired comedian Jay Leno, lit up New York’s Empire State Building using the Microsoft Windows logo colors, and licensed “Start Me Up” by the Rolling Stones as the celebration’s theme song. In the Waterfall lifecycle, the long life of software is acknowledged by a maintenance phase that repairs errors as they are discovered. New versions of software developed in the Waterfall model go through the same several phases, and take typically between 6 and 18 months. The Waterfall model can work well with well-specified tasks like NASA space flights, but it runs into trouble when customers change their minds about what they want. A Turing Award winner captures this observation: Plan to throw one [implementation] away; you will, anyhow. Fred Brooks, Jr. That is, it’s easier for customers to understand what they want once they see a prototype and for engineers to understand how to build it better once they’ve done it the first time. This observation led to a software development lifecycle developed in the 1980s that combines prototypes with the Waterfall model ( Boehm 1986 ). The idea is to iterate through a sequence of four phases, with each iteration resulting in a prototype that is a refinement of the previous version.
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  • Spring '19
  • Dr.Marcos

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