STQA - Past Year 2016

Software Testing Answers

Past Year Questions & Answers 2016

1      1 ai) V-Model concept (10m)

    As defects are found most easily on the same level of abstraction at which they incurred, the right branch assigns each specification or construction step to a corresponding level of testing.

    Component Testing –checks whether each individual software component satisfies requirements of its specification

    Integration Testing – checks whether groups of components as in the technical system design intended operate together

    System testing

    Checks whether the system as a whole meets the specified requirements

    Acceptance /testing – checks whether the system shows the contractually approved performance from a customer perspective

ii)   Relationship between software testing levels in V-model (6m)

    The component testing is testing in every single software component. The integration test checks the interaction of tested components. Functional and non-functional system test consider the whole system from the user point of view. During the acceptance test, the client inspects the product regarding the contractual and user acceptance.

   bi) Pesticide paradox – just repeating tests bring no new insights. Test cases need to be regularly reviewed, revised and modified. (2m)

     ii) Early Testing- Through early testing, which takes place to the parallel of development activities, defects are detected earlier and thus cost less to fix. (2m)

   2a) Difference between system integration testing and functional testing.

Integration	Functional
Test whether the interaction of all components work properly	What the system should perform
Test basis – architecture, workflow, application cases, software and system design	Test basis –req. specification, use-cases, functional specification

  bi) Top down integration (4m)

        The test sequence begins with the component that calls other components, but (except the OS) is not called itself. The lower components are replaced by stubs. Successively, the components of lower system layers are integrated. Each tested higher layer serves as a driver.

 

  ii) Big bang integration (4m)

      The integration waits until all software components have been developed. Then, everything is thrown together at once.In the worst case, upstream component tests are abandoned.     

  c) 2 reasons integration should perform (4m)

     -Detect defects in the interfaces

     -Detect defects in the interaction between components

     -Test non-functional characteristic

  d) 4 main condition that must be analyzed to get optimal integration strategy

          The system architecture – determines which and on how many components the whole system consists of and how they depend on one another.

           The project plan – defines when single components to be developed and when they are ready for testing.

                The test plan/master plan-determines how intensive the system aspects must be tested and at what        specific level

                The test manager –must establish an integration strategy from these conditions which is suitable for the project. This is done in consultation with the project manager.