Big bang integration-All units are linked at once, resulting in complete system. When testing on this system is done it is hard to isolate any problems found as interfaces are not defined properly.
2 . Top down integration-Here system is built in stages starting with components that call other components. Here we go from top to bottom.
Stubs are used in place of components below that are not yet developed.
Bottom down integration-Here we go from bottom to top. Here system is built in stages starting with components that call other components.Buttom components are integrated first as compared to top down integration in which top componets are integrated first.
Drivers are used in place of components above that are not yet developed.