Here we will discuss about the levels of Software Testing. The levels of software testing are:
- Functional Testing
- Non-functional Testing
- FUNCTIONAL TESTING:
As the name suggests Functional Testing, which means this is a type of black box software testing approach used for testing the functionality of the software application. To perform the functional testing, we have to go through each function test by giving the input and getting the output, if the output meets our expected or desired value, then we can say that the function is working properly. Otherwise, the function contains some errors/bugs which needs to be removed for the function to work properly.
Functional testing approach is very useful for testing the software application as it tests each function of the software whether it is working properly or not. While performing Functional testing, the tester has to check only the functionality of the program rather than the source code or the system because it is a type of black box testing.
The main goal of doing functional testing is to test if the entry function or the primary function of the software is working correctly or not, then we have to proceed further by checking the functioning of the Flow of GUI and more proceeding functions which contributes to the overall productivity of the software.
How to perform Functional Testing?
We need to follow the steps for doing Functional Testing:
- The very first step for functional testing is to check and verify the software requirements of the software are correctly provided or not.
- After the verification of the software requirements, the tester has to create a test plan for successful testing approach.
- The tester has to create the test data according to the specification provided in the requirements phase.
- The tester has to execute those test cases for checking the functionality of the program.
- The tester has to check if the desired output is achieved or not, or if there’s any difference in desired output and the actual output.
- After analysis of the both results which are actual output and desired output, the tester has to resolve errors, if there’s any error is found by defect resolving strategies.
TYPES OF FUNCTIONAL TESTING APPROACH:
The functional testing is divided into multiple types of testing approaches. Here we will discuss the types of functional testing:
(a). Unit Testing: Unit testing is a type of functional testing, in which an individual component of the software application is checked or tested for any bugs/errors. The whole program of the software is divided into components and then testing is performed on these components one by one. This testing is very useful as it tests all the components one by one and fix errors in those components.
Though there are some useful applications of unit testing, but apart from them, unit testing cannot find all the bugs in the software. Therefore, it is not possible to make the software completely bugs free in this testing.
(b). Integration Testing: Integration testing is that type of functional testing in which we take a group of components of the software program to perform the testing. Just like we test components in Unit Testing, we just group those components in Integration Testing and do our testing.
Integration Testing has two approaches which are Bottom-up Testing and Top-down Testing.
In bottom-up testing, the testing is started with testing individual components of the program and proceeds further by testing a group of these individual components which are of higher-level program.
In top-down integration testing, the testing is started with higher level program components or a group of components and progressively we test lower-level components at the end.
(c). Smoke Testing: This type of functional testing is used for testing only the basic functionality of the system. Smoke testing is also called as the Build Verification Testing, which is mainly used to test the main functionality of the program.
(d). Regression Testing: This testing is helpful when we are making changes to the code for removing the errors, as this testing tests the effect of changing the code on the functionality of the system. It checks the impacts on the system due to changes made in the code. Regression Testing is very useful because it checks the system functionality which is our foremost part for the software use. It increases the testing approach.
(e). System Testing: System testing is very important part of functional testing because it tests the whole system’s working and the functionality. This testing can be done only after integration testing, because in integration testing, we combine the individual components to check for any error and in system testing, we combine all these integration components into a single component as a complete software for the testing.
(f). Acceptance Testing: Acceptance testing is responsible for Quality Assurance of the software application. Hence, it is the most important testing of all. This type of testing is usually done by developer or the QA team which tests the application if it working as it is desired to function and if it satisfies all the customer’s requirements or not.
(g). Alpha Testing: This testing is done by combining all the three testing approaches which are unit testing, integration testing, and system testing, known as Alpha Testing. This testing approach tests if there are any spelling mistakes or any wrong reference of the functions in the program.
(h). Beta Testing: As the name is Beta testing, it is always performed after successful implementation of the Alpha testing. In beta testing, a group of end-users are invited to test the application’s working. We can also see nowadays in our smartphones which shows that the application is released as a pre-version or the beta version of the app. That app is not deployed completely in the environment, rather it is deployed for some time for testing purposes, before its complete deployment. In this testing, users will install the application, use the application and find if the application is working correct or not. Then based on their analysis and use of the app, they send their feedback to the organization who deployed the app or the developer of the application. Hence, it is very useful approach to test the application software.
ADVANTAGES OF FUNCTIONAL TESTING:
Functional testing is very useful for finding bugs/errors in our software application. Hence, some of the advantages of functional testing are:
- The overall functioning of the software can be tested.
- This testing approach produces a defect-free product, although not a completely bug free product because a software cannot be completely bug free.
- This testing approach ensures that the application is safe to use or not.
- In increases the productivity of the application by removing bugs.
- In ensures that the application is working properly or not.
DISADVANTAGES OF FUNCTIONAL TESTING:
Apart from its features, there are also some disadvantages of functional testing approach which are discussed below:
- Some errors or bugs are missed while performing the tests.
- This testing does not guarantee that the software is completely bug free.
- Redundancy can be increased in this testing.
- It is not sure that the software will go live after performing functional testing, as it does not guarantee that software is working fine.
- NON-FUNCTIONAL TESTING:
In Non-functional testing, we do the testing of those parameters which are non-functional such as the performance of the system and the software, the load test, reliability of the software for the system and the accountability of the software. Non- functional testing is also responsible for testing the user interface and security parameters of the system.
Non-functional testing is only done after performing the functional testing. As the main role of non-functional testing is to give the satisfaction to the customer after testing. Non-functional testing is very important just like functional testing.
How to perform Non-Functional Testing?
To perform non-functional testing, there are several parameters that needs to be tested:
- For load testing, a large number of end users or testers use the application software at the same time and it is tested if the application is affected or not for taking the load of large number of users.
- The user interface is tested if the application performs the desired tasks as per clicks of the user.
- The performance of the application is tested by using the application for a long time and to see if it gives the same performance or the speed became slow after a time period.
- The security parameter is also tested by non-functional testing approach, by using the application like for a transaction if the application provides a secure interface for payment page, then it is considered as secure.
TYPES OF NON-FUNCTIONAL TESTING APPROACH:
The non-functional testing is divided into different types which are also called its parameters. These are:
(a). Load Testing: In this testing approach, the software is tested for the capacity of more uses and its capability that how much time it takes for loading the complete application interface. Load testing is very important for an application’s success because if the application takes time to load for more users using simultaneously the application, then the large number of users will stop using the application.
(b). Performance Testing: This type of non-functional testing approach helps us to test the performance of the application. The software responds slow or fast can be tested by doing performance testing.
(c). Security Testing: The security testing is very important to test the vulnerability of the flaws in the application. This testing is usually done by investigation team of cyber security of the organization. This type of testing helps us to develop a secure application. Therefore, it is very important to perform the security testing on the application.
(d). Portability Testing: Non-Functional testing also tests for the portability of the software for different system architectures. It is very important to check the portability of the application that it can be moved from one system to other system or also it can be used on other system. The portability is very important factor which comes when we need to use our software on another system and we need to move the application to that system.
(e). Accountability Testing: This testing approach is used to test if the system is working correctly or not. The functioning of the software can affect the system’s working; therefore, it becomes essential to perform accountability test on the system and the software.
ADVANTAGES OF NON-FUNCTIONAL TESTING:
There are some advantages of non-functional testing approach which makes it very important for any newly developed software to do Non-Functional Testing on that software:
- Non-Functional Testing is very useful for the security purposes.
- It helps to find flaws which affects the performance of system.
- It takes less time to complete the testing on the software.
- It improves the loading of the software.
DISADVANTAGES OF NON-FUNCTIONAL TESTING:
- We have to perform non-functional tests each time we make changes to the application or update the software.
- Again, if we do tests again, we have to re-fix some errors if encountered, thus it becomes costly.
