Black Box Testing

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Black Box Testing in SDLC

In this article, I am going to discuss Black Box Testing in SDLC. Please read our previous article where we discussed White Box Testing. At the end of this article, you will understand the following important pointers which are related to Black Box Testing in SDLC.

1. What is Black Box Testing in SDLC?
2. What is the Scope of Black Box Testing?
3. Characteristics of Black Box Testing.
4. What kinds of Black Box Testing are There?
5. What are the different types of techniques used in Black Box Testing?
6. How Black Box Testing is Performed in Software Engineering?
7. Which tools are used in Black Box Testing?
8. Why is Black Box Testing Necessary?
9. What are the Advantages of Black Box Testing?
10. What are the Disadvantages of Black Box Testing?
11. Difference between Black Box Testing and White Box Testing

What is Black Box Testing in SDLC?

Software testing methodology known as “Black Box Testing” is employed in the discipline of software engineering. Without requiring knowledge of a software system’s core code or implementation details, it focuses on evaluating its functionality. In other words, the tester examines the system’s inputs and outputs as a “black box,” without having any knowledge of how the system processes the inputs or generates the outputs.

Black box testing’s objective is to find flaws or mistakes in the system’s behavior by giving it different inputs and watching what happens. With this technique, the system is largely validated against its functional specifications, user expectations, and stated needs. It makes sure that the program runs properly from the user’s point of view.

What is the scope of Black Box Testing?

Black box testing makes sure to monitor the input that the software receives while examining the desired outcome. The range of Black box testing is shown below.

• Test your software quickly to ensure the intended purpose is realized.
• Without any prior coding experience with the application, testers can complete this task.
• It aids in testing the software’s functionality.

What are the Characteristics of Black Box Testing?

Black box testing’s salient features include:

1. Lack of Internal Structure Knowledge: When conducting black box testing, testers are not given access to the software system’s source code, internal architecture, or implementation specifics. They only rely on the behavior and external interfaces of the system.
2. Black box testing places a strong emphasis on validating the software system against its requirements and making sure that it accurately carries out the expected functions.
3. Testing Based on Expected Inputs and Outputs: When creating test cases, testers take into account the expected inputs and outputs that the system should generate. When designing test cases, the internal operations of the system are not taken into account.
4. Based on Equivalence Partitions and Border Values, the Following Test Cases: Black box testing frequently uses methods like boundary value analysis and equivalence partitioning to create efficient test cases. Boundary value analysis focuses on evaluating values near the edges of these partitions whereas equivalence partitioning divides the input space into groups with comparable behavior.
5. Verification of Functional and Non-Functional Aspects: Black box testing includes both functional and non-functional components of the software system, such as performance, reliability, and usability. Examples of functional aspects include user interface, data validation, and error handling.
6. Independently Performed: Testers who are not members of the development team can carry out black-box testing. With this independence, the behavior of the software may be evaluated objectively.

What kinds of Black Box Testing are There?

Black box testing can be applied to functional, non-functional, and regression testing, which are the three primary types of tests.

Functional Testing:

Specific features or operations of the software that is being tested can be tested via black box testing. Make sure, for instance, that only the proper user credentials may be used to log in and that the wrong ones cannot. Functional testing might concentrate on the most important features of the software (smoke testing/sanity testing), on how well the system works as a whole (system testing), or on the integration of its essential components.

Non-Functional Testing:

Black box testing enables the examination of additional software components in addition to features and functionality. Non-functional tests focus more on “how” than “if” the software can complete a task. Black box tests reveal whether the software is:

• Accessible to and understandable by its consumers
• Effective under-anticipated or peak loads
• Appropriate for the relevant screen sizes, browsers, operating systems, and/or devices
• Exposed to common security threats or security vulnerabilities.

Regression Testing:

Black box testing can be used to detect whether a new software version exhibits a regression, or a reduction in capabilities, from one version to the next. Regression testing can be used to test both functional and non-functional features of the software, such as when a particular feature no longer functions as expected in the new version or when a formerly fast-performing action becomes much slower in the new version.

What are the different types of techniques used in Black Box Testing?

Black box testing is a method of software testing where the tester does not know the internal structure, particulars of the design, or details of the implementation of the system being tested. Instead, the tester ignores the system’s internal workings and instead concentrates on its inputs, outputs, and behavior. Here are a few typical methods for black box testing:

Here are a few typical methods for black box testing:

• Equivalence Partitioning: This technique involves grouping or partitioning the input data on the grounds that if one test case in a partition shows a flaw, subsequent test cases in the same partition are probably going to behave in the same way.
• Boundary Value Analysis: In this method, test cases are created to assess how the system behaves when input domain boundaries are reached. Testing professionals can improve their chances of discovering flaws by concentrating on values close to the borders, where errors frequently occur.
• Testing Using Decision Tables: Decision tables are used to represent intricate logical connections between inputs and outputs. The combinations of input conditions and related system actions are used to create test cases. By using this method, it is possible to make sure that every combination is covered.
• State Transition Testing: When a system’s behavior is dependent on its present state and inputs, state transition testing is utilized. Test cases are created to simulate various state changes and verify the system’s response at each one.
• Error Guessing: Testers make educated guesses about possible flaws or mistakes in the system based on their knowledge and intuition. Based on this understanding, test cases are created to find flaws that would not be detected by other methods.
• All Pair Testing: Testing of all pairs Technique is employed to test all conceivable discrete value combinations. This combinational approach is used to test applications that incorporate input from checkboxes, radio buttons, list boxes, text boxes, etc.
• Cause-Effect: Cause-Effect The relationship between a particular result and all the factors influencing the result is highlighted by technique. It is founded on a number of conditions.
• Use Case: Case study Technique for locating test cases throughout the system, from the start to the finish, according to usage. Using this method, the testing team develops a test scenario that can put the entire piece of software through its paces based on how well each function works from beginning to end.

How Black Box Testing is Performed in Software Engineering?

The generic steps of Black Box Testing:

1. Due to the fact that it is based on the requirements specification, the black box test is examined first.
2. The tester selects both valid and invalid input values in the second phase to determine whether the program is handling them correctly or incorrectly. He then creates two test scenarios, one positive and the other negative.
3. In the third step, the tester generates a large number of test cases, such as decision tables, all-pair tests, equivalent division, error estimation, cause-and-effect graphs, etc.
4. The fourth phase includes running every test scenario.
5. In the fifth phase, the tester contrasts the actual outcome with the anticipated output.
6. The sixth and final phase involves fixing any bugs in the software and re-testing it.

Which tools are used in Black Box Testing?

The black box testing tools you employ will primarily depend on the kind of black box testing you are performing.

1. Use QTP or Selenium for functional or regression tests.
2. Using LoadRunner and Jmeter, you may do non-functional tests.

Why is Black Box Testing Necessary?

Instead of concentrating on the technical details under different circumstances, it is necessary to understand how a software program behaves. It assists in the identification of various additional faults, including:

• Errors in performance.
• Usability mistakes.
• Functional mistakes.
• Errors in initializing and terminating.
• Issues with concurrency and timing.
• Close the gap in communication.

What are the Advantages of Black Box Testing?

Black box testing, sometimes referred to as behavioral testing or functional testing, is a software testing technique that focuses on analyzing the functionality of the system without having any knowledge of its internal design or implementation specifics. The following are some benefits of black box testing:

1. Independence: Since testers don’t need to understand the internal code, they can operate independently from developers. This encourages a distinct division of labor and lessens bias.
2. Black box testing is simple and doesn’t call for sophisticated technological skills. It is simpler for testers to spot functional errors and issues with the user experience when they concentrate on the system’s inputs and outputs.
3. User-Centric Strategy: Black box testing simulates user behavior to make sure the system satisfies end users’ needs and expectations. It improves the overall quality of the software by validating it from the viewpoint of the user.
4. Comprehensive Testing: Black box testing covers a variety of situations and user routes by testing the system’s functionality without taking into account the underlying code. This aids in finding potential flaws, vulnerabilities, or faults that may go undetected by other testing techniques.
5. Increased Reliability: Errors that influence the system’s overall reliability, such as problems with usability, performance, security, and compatibility, can be found through black box testing. It aids in finding serious flaws before the software is used by end users.
6. Black box testing can be performed early in the development cycle because it doesn’t require an in-depth understanding of the code, which saves time and money. This shortens the whole development process and lowers expenses by enabling quicker feedback and bug resolution.

What are the Disadvantages of Black Box Testing?

Black Box Testing has some drawbacks, including:

1. Lack 0f Understanding: Black box testing restricts the tester’s comprehension of the underlying mechanisms by not offering insights into the internal architecture or code implementation of the system under test.
2. Insufficient Coverage: Test cases are created based on the expected behavior of the system, which may leave out unforeseen events or edge cases that could result in failures.
3. Limited Debugging Capacity: Since testers do not have access to the internal information, it may be difficult to identify the precise reason for a failure or issue, lengthening and complicating the debugging process.
4. Inefficient: Black box testing is inefficient because it frequently necessitates numerous test cases to provide enough coverage, which can be time-consuming and expensive.
5. Repetitive Tests: Black box testing may produce redundant test cases, wasting time and resources because it is impossible to track the test coverage.
6. Limited Security Testing: It is challenging to fully evaluate security flaws and potential attack routes without an understanding of the system’s core architecture.
7. Testing Difficult: Black box testing becomes more difficult when working with complicated systems or testing complex relationships between components since it may not be possible to fully comprehend the system’s behavior based merely on its inputs and outputs.
8. Specification Dependence: Black box testing is very dependent on precise and thorough specifications. The test cases might not cover every feature of the system or might yield inaccurate results if the requirements are lacking or faulty.

Difference between Black Box Testing and White Box Testing

Black Box Testing	White Box Testing
This work is often done by testers.	On it often work with developers.
This kind of software testing conceals the program’s core architecture or source code.	The tester is knowledgeable about the internal architecture and code.
To make it work, you don’t need to write any code.	To make it work, you must write some code.
It is the application’s functional testing.	It involves testing the organizational integrity of an application.
Checking the necessary specification paperwork might be the first step in the testing procedure.	Following the completion of the design document, software testing starts.
Takes very little time.	It might take a while.
The highest layers of software testing benefit the most from this approach.	For simpler software testing, this technique works best.

In the next article, I am going to discuss Grey Box Testing. Here, in this article, I try to explain Black Box Testing in SDLC. I hope you enjoy this Black Box Testing in SDLC article.