This document discusses various software development life cycle (SDLC) models including waterfall, iterative waterfall, rapid prototype, evolutionary, spiral, fish, V-shape, RAD, and incremental models. For each model, it provides a brief description and highlights the advantages and disadvantages. The models differ in their structure, approach to requirements, testing, flexibility, and ability to handle risk and changing requirements.

1. OVER VIEW OF SDLC

2. SOFTWARE DEVELOPMENT LIFE CYCLE

3. DIFFERENT MODELS OF SDLC
Waterfall Model
Iterative Waterfall Model
Rapid Prototype Model
Evolutionary model
Spiral Model
Fish Model
V-Shape Model
RAD Model
Incremental Model

4. WATERFALL MODEL

5. DESCRIPTION:
 Requirements: defines needed information, function, behavior,
performance and interfaces
Design: includes flowcharts, data structures, software
architecture, interface representations, algorithmic details
Implementation: source code, data base, user documentation,
testing.

6. ADVANTAGES OF WF MODEL
 easy to understand, easy to use
 provides structure
 milestones are clear
 good for management control (plan, staff,
track)
 works well when quality is more important
than cost or schedule

7. DISADVANTAGES OF WF MODEL
 all requirements must be known upfront
 deliverables created for each phase are
considered frozen – inhibits flexibility
 can give a false impression of progress
 does not reflect problem-solving nature of
software development , i.e. iterations of
Phases
 one big integration at the end
 little opportunity for customer to preview the
system (until it may be too late)

8. ITERATIVE WATERFALL MODEL

9. DESCRIPTION
This model
 attempts to overcome the limitations of original Waterfall
model by adding an “iterative” loop at the end of the cycle
allows a return to previous stages and the changes whenever
required

10. RAPID PROTOTYPE MODEL
Requirements Capture
Quick Design
Build Prototype
Customer Evaluation of
Prototype
Engineer Final
Product
The Rapid
Prototype Workflow
Iterate

11. ADVANTAGES
 Reduces risk of incorrect user requirements
 Good where requirements are
changing/uncommitted
 Regular visible progress aids management
 Supports early product marketing

12. DISADVANTAGES
 An unstable/badly implemented prototype often
becomes the final product.
 Requires extensive customer collaboration
• Costs customers money
• Needs committed customers
• Difficult to finish if customer withdraws
• May be too customer specific, no broad market

13. EVOLUTIONARY MODEL
Development
Application
User Validation
Feed back
with req.
User Acceptance
N
Y
App is
Base Lined
Initial Reqs.

14. ADVANTAGES
 When costumer is evolving the requirements this is suitable
model

15. DISADVANTAGES
 Dead line are not clearly defined
 Time consuming model
 Costly model
 No transparency
 Project monitoring and maintained is difficult

16. SPIRAL MODEL

17. DESCRIPTION OF SPIRAL MODEL
Key Steps
 Requirement Planning
 Risk Analysis
 Development & Test (Engineering)
 Customer Evaluation

18. DESCRIPTION
 It emphasis more on risk analysis
 In this model project undergoes each phase repeatedly called
spiral
 The planning phase is the base line spiral and each
subsequent spiral built on spiral model
 This types model is used in risk analysis project for ex. Space
Crafts

19. ADVANTAGES
 Importance's is placed more in risk analysis
 Software produced in early stages

20. DISADVANTAGES
 Not suitable for small projects
 IT is very costly
 Need expertise for this model
 Time consuming model

21. FISH MODEL

22. DESCRIPTION
 This is a process oriented company's development model.
 Even though it is a time consuming and expensive model
One can be rest assured that both verification and validation is
done parallel by separate teams in each phase of the model.
 So there are two reports generated by the end of each phase
one for validation and one for verification.
 Because all the stages except the last delivery and
maintenance phase is covered by the two parallel processes the
structure of this model looks like a skeleton between two
parallel lines hence the name fish model.

23. ADVANTAGES
 As the both verification and validation is when outcome will
come quality product
 This strict process results in products of exceptional quality.
So one of the important objective is achieved.

24. DISADVANTAGES
 Time consuming process
 Costly process

25. V-MODEL

26. DESCRIPTION
 A variant of the Waterfall that emphasizes the:
(1).verification and
(2).validation of the product.
 Testing of the product is planned in parallel with a
corresponding phase of development
 Project and Requirements Planning is acceptance testing
 Specification Analysis is systems testing
 Overview/ High-Level Design: defines how software functions
fulfill the design is integration test
 Detailed Design: develop algorithms for each architectural
component is unit test
code

27. ADVANTAGES
 emphasize planning for verification and validation of the
product in early stages of product development
 each deliverable must be testable
 project management can track progress by milestones
 easy to use

28. DISADVANTAGES
Does not
 easily handle concurrent events
 easily handle dynamic changes in requirements
 contain risk analysis activities
 Time consuming model
 Costly model

29. RAD MODEL

30. DESCRIPTION
The phases in the rapid application development (RAD) model are:
Business modeling: The information flow is identified between various
business functions.
Data modeling: Information gathered from business modeling is used to
define data objects that are needed for the business.
Process modeling: Data objects defined in data modeling are converted to
achieve the business information flow to achieve some specific business
objective. Description are identified and created for CRUD of data objects.
Application generation: Automated tools are used to convert process models
into code and the actual system.
Testing and turnover: Test new components and all the interfaces.

31. ADVANTAGES
 Reduced development time.
 Increases reusability of components
 Quick initial reviews occur
 Encourages customer feedback
 Integration from very beginning solves a lot of integration
issues.

32. DISADVANTAGES
 Depends on strong team and individual performances for
identifying business requirements.
 Only system that can be modularized can be built using
RAD
 Requires highly skilled developers/designers.
 High dependency on modeling skills
 Inapplicable to cheaper projects as cost of modeling and
automated code generation is very high.

33. INCREMENTAL MODEL
 Construct a partial implementation of a total system
 Then slowly add increased functionality
 The incremental model prioritizes requirements of the system
and then implements them in groups
 Each subsequent release of the system adds function to the
previous release, until all designed functionality has been
implemented

34. ADVANTAGES
 develop high-risk or major functions first
 each release delivers an operational product
 customer can respond to each build
 uses “divide and conquer” breakdown of tasks
 initial product delivery is faster
 customers get important functionality early
 risk of changing requirements (at the very end) is reduced

35. DISADVANTAGES
 requires very thoughtful planning and design
 requires early definition of a complete and fully functional
system to allow for the definition of increments
 well-defined module interfaces are required (some will be
developed long before others) – to allow for a graceful increment