Black Box Testing Techniques 8 Useful Techniques in Black Box Testing

For example, you could blend use-case testing with decision tables. Black-box testing might also make you less vulnerable to hackers. Some of your tests should involve trying to break past security limitations, and any successful breach indicates that you have more to do to keep your data safe. You might run this form of repeated testing throughout the lifecycle of your product, just to ensure that everything remains secure. If you need input on coding problems, which could make repairs quicker, white-box testing or pen testing might be a better choice. People who work on these teams know all about the code beneath a product, and their tests ensure your product works as you designed it.

Boundary Value testing is useful in reducing/minimizing the number of test cases. Boundary Value testing is most suitable for the systems where input lies within certain ranges. Creating test cases – A unique identification number is assigned to each valid input class, and invalid input class, and then test cases are written with an intention to cover the two sets of input classes. This type of testing is preferred as it helps in minimizing the test cases to a level where the chances of requirement coverage are to an optimum level. There is the Software Testing Life Cycle, that is, STLC, which is of Black box testing, which is relative to each stage of the Software Development Life Cycle.

comments on “Black Box Testing – Definition, types, and techniques”

Testing for Regression − This sort of testing is done after a system maintenance operation, upgrades, or code patches to see how the new code compares to the old code. The test cases for this approach are built by examining the order in which the inputs transition and state or events occur. It’s used when you need to do a lot of testing and you don’t want your inputs to be redundant. It is accomplished by categorizing inputs into classes and assigning a value to each class. This type of testing is entirely dependent on the software’s specs and needs. Safeguard your applications at the edge with an enterprise‑class cloud WAF.

• During the phases of the software testing life cycle, such as regression testing, acceptance, unit, system, integration, and software development, this testing approach is crucial.
• On the other hand white box testing is performed after knowing the internal structure well.
• Black-box testing focuses solely on the functionality of the software interfaces, ensuring that valid inputs are accepted, invalid inputs rejected, and that at all times a correct output is returned.
• The test cases for this approach are built by examining the order in which the inputs transition and state or events occur.
• Software testing is the procedure of evaluating a system with the intent of finding bugs.
• Black Box Test Design Techniques are widely used as a best practice in the industry.

Black box testing gives you a broader picture of the software. In general, following a methodical procedure to test a project/application maintains quality and is valuable in the long term for subsequent rounds of testing. For functional and regression testing, use QTP with Selenium. This method is quite similar to graph-based testing, with the exception that tables are used instead of diagrams or graphs.

The example below demonstrates how these testing methodologies may be used to evaluate particular software with supplied inputs. The methodologies used during Black box testing for a software program are as follows. This technique of testing is also known as behavioral testing or functional testing.

How to do BlackBox Testing

In white-box testing, testers have access to the programmatic structure of the system. Simplifies testing process by focussing only on inputs and outputs. This technique involves testing every single branch from the decision point in the code to be executed at least once to ensure that it is working. Usually hard to achieve 100% code coverage but covering the most important combinations should at least confirm that the code works. The higher the level, and hence the bigger and more complex the box, the more black-box testing method comes into use. Black box testing tools basically depend on what type of black-box testing you are implementing.

Black box testing can be used to check if a new version of the software exhibits a regression, or degradation in capabilities, from one version to the next. Regression testing can be applied to functional aspects of the software , or non-functional aspects . Black box testing can test specific functions or features of the software under test. For example, checking that it is possible to log in using correct user credentials, and not possible to log in using wrong credentials. This technique of Black box testing is widely used to write test cases.

The tester doesn’t need any technical knowledge to test the system. The test cases are run in the system to generate output, which is validated with the expected outcome to mark pass or fail. This method uses the two different versions of the same software to compare and validate the results. For example, a user might enter the password in the wrong format, and a user might not receive an error message on entering an incorrect password.

Error Guessing:

It reduces lots of rework and also gives the good test coverage. We could save lots of time by reducing total number of test cases that must be developed. This type of testing is useful for the testers in identifying the functional requirements of a software or system. This testing method is also referred to as behavioral testing and functional testing. This method of testing is completely based on the specifications and requirements of the software. Tools used for Black box testing largely depends on the type of black box testing you are doing.

Black box testing can check additional aspects of the software, beyond features and functionality. A non-functional test does not check “if” the software can perform a specific action but “how” it performs that action. This testing technique is capable of guessing the erroneous output and inputs to help the tester fix it easily. It is solely based on judgment and perception of the earlier end user experience. Such complex situations rely on decision tables, as it offers the testers an organized view about the inputs combination and the expected output.

Black box testing

On one day in May 2020, thousands of people tried to launch apps on their phones and experienced crashes instead. Black-box testing could have prevented this catastrophic problem. A black-box testing team has no idea how you built the testing subject, so they can’t give you suggestions to fix any problems they find. Their only job is to highlight items that need more investigation. Retest the system using various testing techniques to verify its recurring nature or to pass it.

The next step is to evaluate the set of valid inputs and test scenarios to test the software. This method of designing test cases is about guessing the output and input to fix any errors that might be present in the system. For example, A login page will let you input username and password until three attempts. Each incorrect password will be sent the user to the login page.

As the level is higher, the box would be bigger and more complex, and also, more black-box testing comes into the picture. It is similar to a decision-based test case design approach where the relationship between links and input cases are considered. This testing approach sees an application from a user’s perspective.

In black-box testing, the inner workings of the system are always ‘closed’ to the tester. All positive cases would be from 1 to 100 and we are putting them in a valid partition. Everything below 1 is an invalid value no matter if it is 0 or a negative digit and that is an invalid partition. Everything above 100 is also an invalid partition and every 4 digit number is also an invalid partition. The main thing here is that if we pick one number from a partition to do the testing, the other values from the same partition should have the same output.

Black Box Testing Types

Whenever there are logical conditions or decision-making steps then this technique is to be used. These can be like if a particular condition is not satisfied then Action A should be performed, else Action B is to be performed. The tester needs to identify the input and actions which are to be performed based on the conditions.