Comparison between Testing Phases
Differences in the inter-component dependency: For both
models the inputs are the executable programs indicating the
similarity of the dependence at the beginning of the phase.
Differences in the need for human involvement: For both
models the human involvement is fundamental in the analysis of
the results of the execution of the programs. However the Spiral
Model demands more human involvement since the testing phase
is separated in several interactions.
Differences in the development procedure: The Waterfall Model
has just one task for execution of tests in spite of [9] suggesting
that specialists execute the tests and that all the logics of the
program are tested. In the other hand, the Spiral Model presents a
considerable exploration of the testing phase, being incrementally
conducted in the software for each new interaction.
Differences in scope of issues: Figure 5 shows the detail of the
Spiral Model phases and Figure 2 displays in the third quadrant
the validation through the unit tests, integration and acceptance for
implementation and end of the spiral.
Comparison between Maintenance Phases
Differences in the inter-component dependency: At end of spiral
cycle there is the validation and the customer's evaluation for the
next stage. In this case the Spiral Model presents the dependence
of the customer's evaluation before maintenance what is not
clearly exposed in the Waterfall Model.
Differences in the need for human involvement: The Spiral
Model presents the customer's involvement in the maintenance
phase. That involvement identifies the need for new
improvements or the existence of mistakes.