White box testing and black box testing differ from each other in the fact that black box testing is performed in the absence of any kind of knowledge about the internal organization of the software.
The external monitoring of product functionality is the base for its execution. Thus, if a tester has no requirements or specification for the system and also he has no access to the internal code, then black box testing becomes practically the only way to ensure the correct work of the software product.
This type of testing has several subtypes: functional testing, non-functional testing, and regression testing. The checking can include the system functions, usability, and scalability; in the end, all the errors found by the testers and fixed by the developers are retested.
But any type of testing, additionally to its advantages, has several disadvantages, as none of them can cover absolutely all aspects of the system. Black box testing is not an exception.
Unsatisfactory Peculiarities of Black Box Testing:
- In most cases, the testers should act by guess because of the project configuration gap;
- For the same reason the challenges with the test cases writing appear;
- It may happen that the majority of the important elements can remain unchecked and, thus, many severe errors can be missed.
- There is a great probability that the causes of the found mistake will be not identified.
Regardless of how easy the black box testing method may seem at the first sight, sometimes it cannot guarantee the one hundred percent quality as software testing in the whole range. Thus, it needs to recommend the client, for example, black box testing and white box testing as the fuller package of the quality assurance – it will significantly increase the product chances for success.