test Levels

test Levels

1. Objectives of Testing

   • Acceptance / Qualification Testing
     • determines whether a system satisfies its acceptance criteria
   • Regression Testing
     • selective retesting of a system or component to verify that modifications have not caused unintended effects and that the system or component still complies with its specified requirements.
   • Performance Testing
     • verifies that the software meets the specified performance requirements and assesses performance characteristics
   • Security Testing
     • focused on the verification that the software is protected from external attacks
   • Stress Testing
     • Stress testing exercises software at the maximum design load, as well as beyond it, with the goal of determining the behavioral limits, and to test defense mechanisms in critical systems.
   • Alpha and Beta Testing
     • selected group of potential users for trial use (alpha testing) and/or to a larger set of representative users (beta testing).
   • Reliability Achievement and Evaluation
     • Testing improves reliability by identifying and correcting faults
   • Installation Testing
     • , the software is verified upon installation in the target environment
   • Recovery Testing
     • Recovery testing is aimed at verifying software restart capabilities after a system crash or other “disaster.”
   • Configuration Testing
     • In cases where software is built to serve different users, configuration testing verifies the software under different specified configurations.
   • Usability and Human Computer Interaction Testing
     • The main task of usability and human computer interaction testing is to evaluate how easy it is for end users to learn and to use the software
   • Back-to-Back Testing
     • testing in which two or more variants of a program are executed with the same inputs, the outputs are compared, and errors are analyzed in case of discrepancies
   • Interface Testing
     • Interface defects are common in complex systems

2. System Testing

   • System testing is concerned with testing the behavior of an entire system

3. The Target of the Test

   • The target of the test can vary: a single module, a group of such modules or an entire system.

4. Unit Testing

   • Unit testing verifies the functioning in isolation of software elements that are separately testable

5. Integration Testing

   • Integration testing is the process of verifying the interactions among software components.