INTEGRATION TESTING

SOFTWARE TESTING or SOFTWARE ENGINEERING
INTEGRATION TESTING

1. INTEGRATION
TESTING

2. INTRODUCTION
●A process of testing the interface between two software units or module.

●The purpose of the integration testing is to expose faults in the interaction
between integrated units.

WHY THIS ?

We feel that Integration testing is complex and requires some development and
logical skill. That’s true!
Then what is the purpose of integrating this testing into our testing strategy?

3. How it is done?

●Preparation

●Decide on the type of integration testing approach

●Design test cases.

●Deploy the chosen modules together.

●Track the defects test results

●Repeat

4. CHALLENGES
●Managing integration testing is difficult sometimes.

●Integrating a new system to a legacy system.

●Less compatibility between the two systems developed by two different companies.

●There are way too many different paths and permutations.

5. ADVANTAGES
●The tester can start testing once the modules to be tested are available.

●It detects errors related to the interface between modules.

●Typically covers a large volume of the system.

●Increases the test coverage and improves the reliability of tests.

6. TYPES

7. INCREMENTAL APPROACH
●Incremental Testing is performed by connecting two or more modules together that are
logically related.

●Stubs and Drivers

●Incremental approach is divided into :
1.Top-Down Approach
2.Bottom-Up Approach
3. Sandwich Approach

8. TOP - DOWN APPROACH
●The top-down approach starts by testing the top-most modules and gradually moving down to
the lowest set of modules one-by-one.

9. TOP - DOWN APPROACH
Advantages:
●Separately debugged module.

●It is more stable and accurate at the aggregate level.






Disadvantages:
● Needs many Stubs.
●Modules at lower level are tested inadequately.

10. BOTTOM - UP APPROACH
●The bottom-up approach starts with testing the lowest units of the application
and gradually moving up one-by-one.

11. BOTTOM - UP APPROACH
Advantages:
●In bottom-up testing, no stubs are required.
●Several disjoint subsystems can be tested simultaneously

Disadvantages:
●Requires several drivers

●Data flow is tested very late

12. SANDWICH APPROACH

●It is a combination of Top-down and Bottom-up approaches therefore it is called
Hybrid Integration Testing.

● It makes use of both stubs as well as drivers.

13. SANDWICH APPROACH

Advantages:
●Mixed approach is useful for very large projects having several sub projects.
●This Sandwich approach overcomes this shortcoming of the top-down and bottom-up
approaches.

Disadvantages:
●The cost requirement is very high

●Cannot be used for smaller systems with huge interdependence between the modules

14. BIG BANG APPROACH
●It is the simplest integration testing approach.
●All the modules of the system are simply put together and tested.
●This approach is practicable only for very small systems.

15. BIG BANG APPROACH
Advantages:
●It is convenient for small systems.
Disadvantages:
●Fault localization is tough.

●Critical issues are not resolved on priority.

16. THANK YOU