• 2.  

    No technical standard exists for software architecture; however, the IEEE Software Engineering Standards Committee has created a planning group to investigate the issue. See "Standards Annual Report-1996," located at http://www.computer.org/standard/anreport/toc.htm.

  • 3.  

    Horowitz (1991) emphasizes the importance of architecture; more recently, a Defense Science Board Task Force emphasized the importance of software architecture, and estimated that "a well-formulated architecture might reduce costs of changes/upgrades by 30-50%" (DOD, 1994a).

  • 4.  

    See the contents of the life-cycle architecture milestone and associated rationale in Boehm (1996).

  • 5.  

    While personnel capability and understanding of requirements are also important cost factors, these topics are excluded from the discussion below because they are mostly language-independent variables.

  • 6.  

    This trend is driven by the dual use initiative within DOD (DOD, 1995b) and by legislative changes, namely the Federal Acquisition Reform Act of 1996.

  • 7.  

    One source (Jones, 1995) found that the mean value of source code statements per function point is 71 for Ada 83 and 49 for Ada 95, for a 30 percent reduction. The amount of empirical evidence is small, however.

  • 8.  

    Other sets of criteria would apply for other classes of applications.

  • 9.  

    No independent evaluations of language features were located by the committee, prompting the analysis presented above in the section titled "Technical Evaluation of Ada 95 and Other Third-Generation Programming Languages" and in Appendix B of this report. Most evaluations have been carried out by government agencies or at their direction.

  • 10.  

    Some of the differences in efficiency and risk ratings may be due to increased Ada maturity, but the decline in availability/reliability is more likely due to differences in interpretation of the evaluation criteria.

  • 11.  

    Both of these authors are software consultants; Capers Jones is president of Software Productivity Research Inc., and Donald Reifer, formerly director of DOD's Ada Joint Program Office, is with Reifer Consultants Inc.

  • 12.  

    See Frazier and Bailey (1996) for a recent discussion of STARS demonstration project outcomes.

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