Software Engineering CSC 323

1
Software Engineering - CSC 323

• Introduction

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The state of the practice...

• At a recent computer software engineering course
  in the US, the participants were given an awkward
  question to answer
• "If you had just boarded an airliner and
  discovered that your team of programmers had been
  responsible for the flight control software, how
  many of you would disembark immediately?"
• Among the ensuing forest of raised hands only one
  man sat motionless. When asked what he would do,
  he replied that he would be quite content to stay
  on board. With his team's software, he reasoned,
  the plane was unlikely to even taxi as far as the
  runway, let alone take off.

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Software development...

• Art?
• ...Craft?
• or Science?

4
Problems BEFORE Software Engineering

• Late projects
• Cost overruns
• High maintenance costs
• Unreliable, inaccurate systems
• Poor project control
• Poor traceability of requirements
• Unpredictable development process

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Origins of Software Engineering

• 1967 - NATO study group coins term
• 1968 - NATO conference Garmisch, Germany
• 1969 - Conference in Rome, Italy

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Problems AFTER Software Engineering

• Late projects
• Cost overruns
• High maintenance costs
• Unreliable, inaccurate systems
• Poor project control
• Poor traceability of requirements
• Unpredictable development process

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Definitions of Software Engineering

• The establishment and use of sound engineering
  principles in order to obtain economically
  software that is reliable and works efficiently
  an real machines."
• Naur, P., and S. Randall, eds. Software
  Engineering -A Report an a Conference Sponsored
  by the NATO Science Committee. NATO, 1969
  quoted in Roger S. Pressman,
• Software Engineering A Practitioner's Approach.
  New York McGraw-Hill Book Company. 1987.

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Definitions of Software Engineering

• the technological and managerial discipline
  concerned with systematic production and
  maintenance of software products that are
  developed on time and within cost estimates.
• - Fairley, Richard E. Software Engineering
  Concepts. New York McGraw-Hill, 1985

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Definitions of Software Engineering

• The disciplined application of engineering,
  scientific, and mathematical principles, methods,
  and tools to the economical production of
  quality software.
• -Pressman, Roger S. Software Engineering A
  Practitioner's Approach. New York McGraw-Hill
  Book Company. 1987.

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Definitions of Software Engineering

• . . .software engineering is a discipline whose
  aim is the production of fault-free software,
  delivered on time and within budget, that
  satisfies the users needs.
• Schach, Stephen R. Object-Oriented and Classical
  Software Engineering . 6th ed., New York
  McGraw-Hill. 2005.

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Definitions of Software Engineering

• (1) The application of a systematic,
  disciplined, quantifiable approach to the
  development , operation, and maintenance of
  software that is, the application of engineering
  to software. (2) The study of approaches as in
  (1).
• - IEEE Standards Collection Software
  Engineering, IEEE Standard 610.12-1990, IEEE,
  1993.

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Definitions of Software Engineering

• Software Engineering The process by which all
  fun is removed from computer programming.
  -Anonymous