Intra-Module, Inter-Module and External Interfaces

It is imporatnt to understand the difference between Intra-Module, Inter-Module and External Interfaces.

Let's try the same with following Typical System Diagram:


Inter modular interface - Between units within a module

Intra modular interface - Between modules within a system/application

External interface - External systems/applications

Stubs and Drivers

Stubs and drivers would be required to simulate modules and facilitate interface testing during integration.

Stubs can be as simple as routines that automatically return on a call, or they can be more complicated and return simulated results.

Test drivers provide the facilities needed to execute a program (e.g., input or files, commands).

Test drivers permit generation of data in external form to be entered automatically into the system.

Next is Approach for Testing Interface.