CSC307 Lecture 02

Introduction to Software Engineering
Process Models
(202306)

Transcript

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   CSC 307
   Introduction to Software Engineering
   Lecture 02:
   Processes Models
   Dr. Javier Gonzalez-Sanchez
   javiergs@calpoly.edu
   www.javiergs.com
   Building 14 -227
   Office Hours: By appointment
   

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2. CSC 308 | Dr. Javier Gonzalez-Sanchez | 2
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   Key Ideas
   Good software is software
   that compiles and run
   

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3. CSC 308 | Dr. Javier Gonzalez-Sanchez | 3
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   Key Ideas
   ❌ Good software is software
   that compiles and run
   

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4. CSC 308 | Dr. Javier Gonzalez-Sanchez | 4
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   Key Ideas
   Large vs Small
   Human-Centered
   for
   Modifiability
   Extensibility
   Together but not
   scrambled
   Quality
   Cost
   

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5. CSC 308 | Dr. Javier Gonzalez-Sanchez | 5
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   CSC 307
   Introduction to
   Software Engineering
   Definition
   

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6. CSC 308 | Dr. Javier Gonzalez-Sanchez | 6
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   “The application of a
   systematic, disciplined, quantifiable
   approach to the
   development, operation, and maintenance of
   software”
   – IEEE
   Software Engineering
   

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7. CSC 308 | Dr. Javier Gonzalez-Sanchez | 7
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   “The application of a
   systematic, disciplined, quantifiable
   approach to the
   development, operation, and maintenance of
   software”
   – IEEE
   Software Engineering
   Process
   

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8. CSC 308 | Dr. Javier Gonzalez-Sanchez | 8
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   process
   activity
   activity
   activity
   activity
   Definitions
   step step step step
   step
   step
   step
   step
   step
   step
   step
   step
   step step step step
   step
   

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9. CSC 308 | Dr. Javier Gonzalez-Sanchez | 9
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   § Communication or Requirement Engineering
   § Modeling or Design
   § Construction or Implementation
   § Testing (Unit, UI, Integration, Stress, Regression)
   § Deployment or Delivery
   Activities
   

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10. CSC 308 | Dr. Javier Gonzalez-Sanchez | 10
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    Homework
    § http://taiga.io (mandatory)
    § https://astah.net (mandatory)
    § https://www.jetbrains.com/idea/ (optional)
    § https://github.com (mandatory)
    

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11. CSC 308 | Dr. Javier Gonzalez-Sanchez | 11
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    How to connect the activities?
    

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12. CSC 308 | Dr. Javier Gonzalez-Sanchez | 12
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    § Plan-driven all process activities are planned in advance and progress is
    measured against a plan (a contract).
    § Agile, planning is incremental and it is easier to change the process to
    reflect changing customer requirements.
    Strategy
    

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13. CSC 308 | Dr. Javier Gonzalez-Sanchez | 13
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    Plan-Based Models:
    • Waterfall
    • V-model
    • Incremental
    • Spiral
    • Prototype
    Examples
    Agile Methodologies:
    • SCRUM
    • Kanban
    • XP (extreme programming)
    • Feature Driven
    Development
    

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    Plan-based Process
    

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15. CSC 308 | Dr. Javier Gonzalez-Sanchez | 15
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    • Waterfall
    • V-model
    • Incremental
    • Spiral
    • Prototype
    Plan-based Process Models
    

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16. CSC 308 | Dr. Javier Gonzalez-Sanchez | 16
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    The Waterfall Model
    

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17. CSC 308 | Dr. Javier Gonzalez-Sanchez | 17
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    § Key idea: Separate and distinct phases of specification and development. A
    phase has to be complete before moving onto the next phase.
    § Type: Linear model.
    § Recommended for: Embedded systems and Large systems(developed by
    several partner companies)
    § Disadvantage: difficulty of accommodating change after the process is
    underway.
    The Waterfall Model
    

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18. CSC 308 | Dr. Javier Gonzalez-Sanchez | 18
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    The V-Model
    this arrows point at
    what we are testing
    

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    § Key idea: It is an extension of Waterfall where instead of moving down in a
    linear way, the process steps are bent upwards after the coding phase.
    While tests are just one of five steps in Waterfall, it looks like practically
    half of the process in V-model.
    § Type: Linear model.
    § Recommended for: well-suited for projects that must maintain a strict
    deadline and meet key milestone dates throughout the process.
    Example: medical device industry
    § Disadvantage: same that waterfall
    The V-Model
    

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20. CSC 308 | Dr. Javier Gonzalez-Sanchez | 20
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    The Incremental Model
    Option A: Linear Increments (not all colors (activities) are repeated)
    

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21. CSC 308 | Dr. Javier Gonzalez-Sanchez | 21
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    The Incremental Model
    Option B: Parallel Increments (most than 1 activity at the same time)
    

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    § Key idea: split each activity in pieces.
    § Type: Iterative model (it could include parallel).
    § Recommended for: Facilitate getting customer feedback on the
    development work that has been done.
    § Disadvantages: (1) it could not cost-effective to produce documents that
    reflect every version of the system; (2) System structure tends to degrade
    as new increments are added. Unless time and money is spent on
    refactoring to improve the software, regular change tends to corrupt its
    structure.
    The Incremental Model
    

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23. CSC 308 | Dr. Javier Gonzalez-Sanchez | 23
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    Prototyping
    Construction
    of prototype
    communication
    Quick
    plan
    Modeling
    Quick design
    Construction
    of prototype
    Deployment
    delivery &
    feedback
    

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24. CSC 308 | Dr. Javier Gonzalez-Sanchez | 24
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    § Definition: a prototype is an initial version of a system used to demonstrate
    concepts and try out design options.
    § Evolutionary model
    § Recommended for: a prototype can be used to help with requirements
    elicitation and validation; or in design processes to explore options and
    develop a UI design.
    Prototyping
    

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25. CSC 308 | Dr. Javier Gonzalez-Sanchez | 25
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    The Spiral Model
    

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26. CSC 308 | Dr. Javier Gonzalez-Sanchez | 26
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    § Key idea: High amount of risk analysis hence, avoidance of Risk is
    enhanced.
    § Evolutionary model
    § Recommended for: (1) Good for large and mission-critical projects. (2)
    Strong approval and documentation control. (3) Significant changes are
    expected (research and exploration).
    § Doesn’t work well for smaller projects.
    § Doesn’t work well when users are unsure of their needs
    § Doesn’t work well when requirements are complex
    The Spiral Model
    

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    Agile Methods
    To be continued…
    

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28. CSC 308 | Dr. Javier Gonzalez-Sanchez | 28
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    Chapter 1, 2 and 3
    References
    

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29. CSC 308 | Dr. Javier Gonzalez-Sanchez | 29
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    Questions
    

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30. CSC 308 | Dr. Javier Gonzalez-Sanchez | 30
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    Office Hours
    Tuesday and Thursday 3 - 5 pm
    But an appointment required
    Sent me an email – javiergs@calpoly.edu
    

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    CSC 307 Introduction to Software Engineering
    Javier Gonzalez-Sanchez, Ph.D.
    javiergs@calpoly.edu
    Summer 2023
    Copyright. These slides can only be used as study material for the class CSC307 at Cal Poly.
    They cannot be distributed or used for another purpose.
    

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