Model Base Validation Techniques for Software

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Model Base Validation Techniques for Software

• Insup Lee

SDRL (Systems Design Research Lab) RTG
(Real-Time Systems Group) Department of Computer
and Information Science University of
Pennsylvania Philadelphia, PA
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PITAC report

• Presidential Information Technology Advisory
  Committee (PITAC) report to the President, Feb
  1999.
• www.hpcc.gov/ac/report/
• Finding and Recommendations
• Federal information technology RD investment is
  inadequate.
• Federal information technology RD is too heavily
  focused on near-term problems.
• Recommendation  Create a strategic initiative in
  long-term information technology RD.

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Technical Research Priorities

• Software Research
• Scalable Information Infrastructure
• High-End Computing 
• Socioeconomic Impacts 
• Creating Effective Management Structure for
  Federal IT RD

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Software Research

• Findings
• Demand for software far exceeds the Nation's
  ability to produce it.
• The Nation depends on fragile software.
• Technologies to build reliable and secure
  software are inadequate.
• The diversity and sophistication of software
  systems are growing rapidly.
• More and more often, common activities of
  ordinary people are based on software.
• The Nation is underinvesting in fundamental
  software research.
• E.g., Space shuttle, Arian 5, Denver airport,
  etc.

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Software Research

• Recommendations
• Make fundamental software research an absolute
  priority
• Fund fundamental research in software development
  methods and component technologies.
• Support fundamental research in human-computer
  interfaces and interaction.
• Support fundamental research in information
  management techniques for managing, analyzing,
  and explaining information and in making it
  available for its myriad of uses.
• Make software research a substantive component of
  every major IT research initiative.
• Increase current funding for software research as
  follows over fiscal years 2000-2004. (112M,
  268M, 376M, 472M, 540M)

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New Research Directions for Software

• Model-based software development
• Multi-faceted programming
• Composable and customizable frameworks
• Collaborative software development
• Intelligent middleware
• Design of networked embedded systems
• System/Software co-design environment

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Model-based software development

• Research goal to move software development
  toward the use of high-level, domain-specific
  abstractions in the development process.
• These high-level, domain-specific modeling
  languages must be formal enough to be used
  directly for
• analysis of designs and
• software generation.
• Model-based software development technologies
  should also support a wide range of new
  capabilities such as self-monitoring,
  self-healing, self-adaptation and
  self-optimization.

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Models in Traditional Engineering

• Before we build the real thing...

and then evaluate them
we first build models
Selic
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Software Models

• Abstract representations of programs that
  highlight properties of interest
• Models help us to reason about a software system
• Expressed using problem domain concepts (vs.
  implementation/technology domain concepts)

subsystem subXY () int x,y for I 1 to 55
do xI yI1 case xI of 1
if (xI . . .
Software is the only engineering medium in which
models can be evolved into complete
implementations
Selic
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Software Development Process

• Requirements capture and analysis
• Informal to formal
• Consistency and completeness
• Assumptions and interfaces between system
  components
• Application-specific properties
• Design specifications and analysis
• Formal modeling notations
• Abstractions
• Analysis techniques (simulation, model checking,
  equivalence checking, testing, etc.)
• Implementation
• Manual/automatic code generation
• Validation (testing, model extraction, etc.)
• Run-time monitoring and checking

Requirements
Design specification
Implementation
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Q A