Traditional Testing Cycle

Let us look at the traditional Software Development life cycle. The figure below depicts the same.

In the above diagram (Fig A), the Testing phase comes after the Coding is complete and before the product is launched and goes into maintenance.

But, the recommended test process involves testing in every phase of the life cycle (Fig B). During the requirement phase, the emphasis is upon validation to determine that the defined requirements meet the needs of the project. During the design and program phases, the emphasis is on verification to ensure that the design and programs accomplish the defined requirements. During the test and installation phases, the emphasis is on inspection to determine that the implemented system meets the system specification.

The chart below describes the Life Cycle verification activities.


Throughout the entire lifecycle, neither development nor verification is a straight-line activity. Modifications or corrections to a structure at one phase will require modifications or re-verification of structures produced during previous phases.