Software Testing - Grey Box Testing

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Software testing is a combination of the black box, white box, and the gray box testing techniques. While the black box testing is only concerned with the external working of the software, the white box testing is all about verifying only its internal structure, and the gray box testing is a combination of both the black box and the white box testing.

What is Gray Box Testing?

The gray box testing is the one which merges both the black box testing and the white box testing approaches. For the black box testing, the testers are unaware of the interiors of the software and for the white box testing, they are well versed with its internal characteristics. Thus for the gray box testing, only the partial software interiors comprising the data structures are verified.

A gray box testing is named like this because the testers do not have the full understanding of the interior working of the software but they have a partial knowledge(reflecting combination of black and white to form a gray box). It is mainly centered around verifying the context specific errors generated in the software.

Objectives of the Gray Box Testing

The objectives of the gray box testing are listed below −

• It reaps the benefits of both the black and white box testing techniques.
• It takes into consideration the knowledge of both the developers and the testers.
• It helps in enhancing the software quality.
• It eliminates the lengthy process of completing both the functional and non-functional testing.
• It provides a lot of time for developers to resolve errors in the software.
• It is conducted from the end user perspective rather than from the software design.

Techniques Followed in the Gray Box Testing

The techniques followed in the gray box testing are listed below −

Matrix Testing

In this type of testing, the developers identify the potential technical, and business risks in the software and then verify them.

Pattern Testing

All the defects detected in the previous cycle of testing are examined and their root causes are identified from the code. All the causes of errors are then converted into test cases.

Orthogonal Array Testing

In this type of testing, every combination of inputs are considered for testing the software. It is basically based on the black box testing technique. It is performed when there is a shortage of the number of test cases and the test data range is huge. This technique helps to acquire maximum test coverage by covering a big range of inputs for the software.

Regression Testing

This type of testing is done to verify if the latest code changes have not introduced new defects. Thus it confirms if the existing features in the software are working as expected.

State Transition Testing

This type of testing is applied for software which undergoes multiple changes to its state in its complete working. The testers having knowledge of the intermediate states that the software goes through create test cases covering all of them.

Decision Tables

The decision tables help in summarizing all the business rules that the software needs to adhere to. They assist the testers to create tests involving various combinations of data and corresponding outputs that they generate.

API Testing

The gray box testing is mostly conducted to verify all the APIs having different combinations of payloads and their responses.

Data Flow Testing

This type of testing is primarily focussed on verifying the flow, path, filtering and communication of data across the whole software.

Advantages of Gray Box Testing

The advantages of the gray box testing are listed below −

• The developers and testers are fully aware of the expectations from them while testing the software.
• It is performed from the customer’s viewpoints.
• It does not require extensive technical and coding knowledge from the testers.
• It helps in enhancing the overall quality of the software.
• The developers get more time to fix defects encountered while doing gray box testing.
• It amalgamates the benefits of both the black and white box testing methodologies.
• It does not create a situation where the testers and developers share opposite views on the same topic.
• It is found to be more productive than performing simple integration testing on the software.

Disadvantages of Gray Box Testing

The disadvantages of the gray box testing are listed below −

• Defect isolation is not easy while gray box testing is applied on a distributed software.
• The testers do not have full access to the software code along with its paths and structures.
• It cannot be used to test algorithms on which the software is built.
• It is not easy to create test cases exclusive for the gray box testing.

Conclusion

This concludes our comprehensive take on the tutorial on Software Grey Box Testing. We’ve started with describing what is gray box testing, what are the techniques followed in the gray box testing, advantages and disadvantages of the gray box testing. This equips you with in-depth knowledge of Software Grey Box Testing. It is wise to keep practicing what you’ve learned and exploring others relevant to Software Testing to deepen your understanding and expand your horizons.