The incremental model divides a project into a series of increments. Each increment follows the waterfall model by going through planning, modeling, design, construction, testing, and deployment phases to deliver working functionality. As increments are completed, the working system is expanded until the full system is implemented. This allows software to be delivered in early increments while maintaining flexibility to change scope over the course of the project. However, problems can arise if not all requirements are identified upfront.

2. Basic idea of incremental model
DEVELOPING A SOFTWARE SYSTEM
INCREMENTALLY FOR TAKING ADVANTAGE OF
WHAT WAS BEING LEARNED DURING THE
DEVELOPMENT OF EARLIER, INCREMENTAL,
DELIVERABLE VERSIONS OF THE SYSTEM BY DIVIDING
PROJECT TO ITERATIONS OR INCREMENTS

3. ITERATIVE AND INCREMENTAL
DEVELOPMENT
 is a cyclic software development model
developed in response to the weaknesses of
the water fall model.
 approach attempts to combine the waterfall
sequence with some of the advantages of
prototyping.
 This approach favored by object oriented
practitioners.

4. INCREMENTAL MODEL LIFE CYCLE

5. THE INCREMENTAL MODEL
 increment #n
Software functionality and features
communications
planning Modeling
analysis design
Construction
Deployment
code test
delivery
feedback
 Increment #2 Delivery of nth increment
communications
planning
Modeling analysis
design Construction
 Increment#1 code test Deployment
delivery
feedback
Delivery of 2nd
increment
communication
planning Modeling analysis
Construction
design Deployment
code test
delivery feedback
Delivery of 1 st increment
Project calendar time

6. INCREMENTAL MODEL LIFE CYCLE
 It basically:
 divides the overall project into a number of increments.
 Then it applies the waterfall model to each increment.
 The system is put into production when the first increment is delivered.
 As time passes additional increments are completed and added to the working
system
 Notes:
 Phases on each increment are sequential.

7. CONT…………
 key process are to start with a simple implementation of a subset of the
software requirements and iteratively enhance the evolving sequence of
versions until the full system is implemented.
 At each iteration, design modifications are made and new functional
capabilities are added.

8. ADVANTAGE & DISADVANTAGES
 Generates working software quickly and early during the software life cycle.
 More flexible - less costly to change scope and requirements.
 Easier to test and debug during a smaller iteration.
 Easier to manage risk because risky pieces are identified and handled during its
iteration.
Disadvantages:
 Each phase of an iteration is rigid and do not overlap each other.
 Problems may arise pertaining to system architecture because not all
requirements are gathered up front for the entire software life cycle.

9. FINALLY………
 success or failure of the software projects greatly depends
on right chosen of software development lifecycle
model.
Always choose the one that achieve your goals , vary models
and put your touch on your choice to make creative system .