Software Engineering Process

1. Software Processes
Elliot Attipoe
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2. Objectives
• To introduce software process model
• To introduce 3 generic software process
models
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3. The software process
• A structured set of activities required to develop a
software system
– Specification
– Design and implementation
– Validation
– Evolution
• A software process model is an abstract
representation of a process.
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4. Generic software process models
• The waterfall model
– Separate and distinct phases of specification and
development
• Incremental (Evolutionary) development
– Specification and development are interleaved
• Reuse-oriented software engineering
– The system is assembled from existing
components
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5. Waterfall model
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6. Waterfall model problems
• Inflexible partitioning of projects into distinct stages.
• Difficult to respond to changing customer
requirements.
• This model is only appropriate when requirements
are well-understood.
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7. Incremental Development
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8. Benefits compared to waterfall
• Cost of accommodating changing customer
requirements.
• Easier to get customer feedback
• Rapid delivery and deployment of useful
software to the customer.
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9. Disadvantages
• The process is invisible.
• System structure tends to degrade as new
increments are added.
• Not good for critical systems which needs a
stable framework or architecture.
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10. Applicability
• For small or medium-sized interactive
systems.
• For parts of large systems (e.g. user
interface).
• For short-lifetime systems.
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11. Reuse-oriented software
engineering
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12. Process Activities
• Software specification
• Software design and implementation
• Software validation
• Software evolution
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13. Software Specification
• The process of establishing what services are
required and the constraints on the system’s
operation and development.
• Requirements engineering process
– Feasibility study
– Requirements elicitation and analysis
– Requirement specification
– Requirement validation
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14. Requirements engineering process
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15. Software design and Implementation
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16. Software validation
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17. Software Validation
Time
Cost to fix
error
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18. Software Evolution
• Coping with change
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19. Reading Assignment
• Prototyping - pp 45
• Spiral model – pp 48
• The rational unified process - pp 50
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20. Group Assignment (Project proposal)
• Each group is to come up with any project (software product)
they think is interesting and valuable.
• The project should have some connection to real world.
• The project can be a web application, an android application or a
desktop application.
• It is your responsibility to make sure that the project can be
built, making use of the available resources and technology to
you.
• The project should be of suitable size to be completed (including
design, testing and documentation) in 7 weeks.
• Due date : 1st Oct. 2013
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