In general, whenever software engineers speak about software testing, they’re likely referring to the functional tests that are applied to a system. However, there is another type of test that is equally important for the certification of quality software: non-functional tests. These measure non-functional aspects such as performance, usability, reliability, etc.
Why Is This Type of Test So Important?
Test execution is a critical phase in the process of software quality certification. These tests must be exhaustive so that the established standards are met and the software’s quality is guaranteed. Therefore, functional tests - those that make certain the system functions as required - are not enough. In addition to functional tests, it is of the utmost importance to include non-functional tests in the process. When applying the latter, indispensable aspects beyond functionality are certified to ensure a high-quality product (such as reliability, efficiency, maintainability, and portability).
These include tests that validate aspects outside the system’s functional flows. Some examples:
- Load testing
- Performance testing
- Volume testing
- Stress testing
- Stability testing
- Robustness testing
- Compliance testing
- Usability testing
How Do These Tests Contribute to Software Quality Assurance?
Among other contributions, the types of tests mentioned above provide essential information concerning:
- How the system will behave once it is put to use
- How many simultaneous users the system can handle
- How many requests the system is prepared to receive
- The minimum equipment requirements needed to utilize the system
- How the system will respond to hardware failures
- System behavior when processing a large amount of data
- The maximum amount of supported transactions
- How the system will respond to overload
- How the system will respond to incorrect inputs or unspecified data
In addition, usability and compliance testing guarantee the software adheres to external as well as internal norms and regulations. They also make sure the final product is structured and can be understood by the user.
Lastly, other non-functional aspects that enhance the final diagnosis include maintainability, stability, testability, adaptability, modifiability, installability, and other aspects that help to determine the system’s quality.
In conclusion, including non-functional tests in the quality assurance process adds value, provides information, and assures reliability. For this reason, it is recommended that this type of test be considered at the start of a QA cycle.