This presentation describes the diferences between Iterative and Incremental development and how both combined lead to success at agile development. Furthermore it explains how requirements shoudl be broken down in smaller parts to support incremental iterative development.

1. Oliver Schreck, 2012

2. Rough overview of picture
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3. Iterative Development
 Develop, then evaluate, then change, …
 Never expected it to be right.
 Iterate to find the right solution.
 Given some good candidate solution, we might then
iterate to improve a candidate solution.
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4. Iterative Development
 Wikipedia:
 Iteration means the act of repeating a process usually
with the aim of approaching a desired goal or target or
result. Each repetition of the process is also called an
“iteration”, and the results of one iteration are used as
the starting point for the next iteration.
 The whole product is iterated all the time.
(This of course is in the purest iterative, non-incremental case)
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5. 1st Iteration
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6. 2nd Iteration
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7. 3rd Iteration
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8. 4th Iteration
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9. Incremental development
 Incrementally add software a time
 Build up functionality gradually
 Release incrementally so that we actually get that
business value we're chasing.
 We don't really get return on investment till people
begin to use the software we've built.
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10. Incremental development
 Wikipedia:
 Incrementalism is a method of working by adding to a
project using many small, incremental changes instead
of a few (extensively planned) large jumps.
 It means you develop one part of the system and when
it’s ready you develop the next part
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11. 1st Increment
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12. 2nd Increment
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13. 3rd Increment
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14. 4th Increment
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15. Putting both together all the phases of
 Incremental development goes through
development (analysis, testing, development, design,
integration, production) it is a perfect tool to expose all
problems in the process.
 Incrementalism improves the process and
adds new topics.
 Iterative process means rework on the existing product.
 Iterativity improves the product
 Both can be used without each other but they can be used
together as well.
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16. 1st Increment and 1st Iteration
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17. 1st Increment and 4th Iteration
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18. 2nd Increment and Xth Iteration
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19. 3rd Increment
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20. 4th Increment
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21. The different flavors
 Waterfall is non-
iterative, non-
incremental process
 Staged delivery is
incremental but not
iterative
 Spiral model is highly
iterative but not at all
incremental
 Agile process has
many different
flavors, amount of
iterative and
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22. Document level
 Requirement  What to do rough?
Specification (Customer
req.)
 How to do rough?
 System Specification
(System req.)
 What to do in detail?
 Feature Specification
(Feature req.)
 Design Specification  How to do in detail?
(Design req.)
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23. Requirement Specification – What to do rough?
CR CR CR
Customer View
Viewer Filming Service
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24. System Specification – How to do rough?
CR CR CR
System
Architecture View
Viewer Filming Service
Front End System req.
Back End System req.
Services System req.
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25. Feature Specification – What to do in detail?
CR CR CR
Customer View
Load Images
Zoom
Viewer Filming Service
Front End System req.
Feature req.
Feature req.
Back End System req.
Services System req.
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26. Design Specification – How to do in detail?
Customer req.
Design
Load Images
Feature req.
Feature req.
Zoom
Architecture View
Design req.
Front End System req.
Design req.
Viewer
Design req.
Design req. Back End System req.
Design req.
Services System req.
Design req.
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27. After Multiple Iterations
Customer req.
Viewer
Design req. Front End System req.
Design req.
Back End System req.
Design req.
Design req. Services System req.
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28. Questions?
If (unclear == true) then askme();
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