Here are a small listing of the basic integration strategies a test manager can use when he’s designing a test strategy:
Top-down integration:
The test starts with the top level component of the system that calls the components but is not called itself (the top component).
Stubs must substitute all non-finished lower-level components, integration proseede with the lower-leel components as soon as they are produced.
Advantage: Test drivers are not needed, the highere-level components are the test-drivers.
Disadvantage: This is a very costly method, because of the amount of stubs to be produced.
Bottom-up integration:
the test start with the elementary system components that do not call further components.
Advantage: Nu stubs are needed.
Disadvantage: Test drivers must be produced to simulate the higher-level components.
Ad-hoc integration:
The components are being integrated as they are finished.
Advantage: This saves time, beeause every component is integrated as early as possible.
Disadvantage: Both stubs and test drivers are required.
Backbone integration strataegy:
A backbone or skeleton is built into which components are gradually integrated.
Advantage: Components can be integrated in any order.
Disadvantage: Backbone is required,production of this is labor-intensive.