Difference - Incremental and Integration Testing

What is the difference between Incremental and Integration Testing. It is very confusing, to find the difference. Can anyone elaborate on the same.:)

Hi Rajiv,

Increamental testing is a way of integration testing in which first you test each module of the software indiviually then continue testing by adding another module to it then another.

Integration Testing is an tegration testing strategy in which you test subsystems in isolation, and then continue testing as you integrate more and more subsystems".

[U]Types[/U]
Bottom Up Testing : In this you start by testing the very lowest levels of the software using drivers, and then work upwards, as you integrate successive layers


Top - Down Testing : start by testing only the user interface, with the underlying functionality simulated by stubs, then you work downwards, integrating lower and lower layers

Iintegration testing in general is testing the functional flow in terms of Dataflow as well as the capability of modules to work with one another.

Cheers...

Hi Rajiv,

Few more points on Incremental and Integration Testing which will helps you in understading better:

<u>Incremental Testing:</u>

Incremental Testing is a method of testing the interfaces between unit-tested programs as well as between system components. The testing process here is done by adding unit tested module (or program) to a given module or component one by one and testing each result and combination.

Incremental testing has two types:

a. Top down begins testing from the top of the module and work down to the bottom using interim stubs to simulate lower interfacing modules. Modules are added in descending hierarchical order

b. Bottom up begins testing from the bottom of the hierarchy and works up to the top. Modules are added in ascending order. This testing requires the development of driver modules which provide the test input, call the module or program being tested and display test output.

Most of the time bottom up approach is used as it is easier to create drivers than stubs.

<u>Integration Testing:</u>

Integration testing refers to the testing in which software units of an application are combined and tested for a communication interfaces between them. Integration testing is done by three ways:

1. <b>Big bang approach:</b> Every module is unit tested in isolation from every module and then each module combined all at a once and tested.

2. <b>Bottom up approach:</b> All the modules are added from lower level hierarchy to higher level where the lower model is tested in isolation then the next set of higher modules are tested with integrating the already unit tested lower module.

3. <b>Top down approach:</b> Which is a reciprocate of the bottom up model where the the higher model is tested in isolation then the next set of lower modules are tested with integrating the already unit tested higher module.

Hope this would have made you clear.