What is System Testing?
System testing, also called system-level testing or system Integration Testing, is the process in which a quality assurance team evaluates how the various components of an application interact together in the whole, integrated system or application. System testing verifies that an application performs tasks as designed. It’s a type of black box testing that focuses on the functionality of an application rather than the inner workings of a system which white box testing is concerned with. System testing may check that every user input produces the intended output across the application. System testing is the third level of testing in the software development process. It’s typically performed before acceptance testing and after integration testing.
Importance of System Testing
System testing is imperative for interconnected systems because any system or software defect can cause extreme consumer complications.
The following are the main benefits of system testing:
- It has improved product quality. A comprehensive system testing process ultimately boosts product quality. Since an integrated system is tested through multiple test sets in a product development cycle, it provides a glimpse into whether a product can successfully work across different platforms and environments.
- Error reduction. Some errors are bound to happen during the development of complex systems. System testing verifies a system’s code and functionality against its requirements, so errors not detected during integration and unit testing can be exposed during system testing.
- Cost savings. It can be more time-consuming to fix a system defect that’s detected later in the project lifecycle. Conducting timely and continuous system testing reduces unexpected costs and project delays and provides project managers with better budget control.
- Security. Well-tested products are reliable. They ensure that the tested system doesn’t contain potential vulnerabilities that can put end users and system data at risk of potential threats.
- Customer satisfaction. System testing offers visibility into the stability of a product at every stage of development. This builds customer confidence and improves the overall user experience.
- Easier code modification. System testing can identify code problems during software development. Fixing older code that has gone into the production environment is much more complicated than modifying it while it’s still in development.
- Software performance. Performance-based system tests can help understand changes in a system’s performance and behavior, such as memory consumption, central processing unit utilization, and latency. These tests raise red flags if system performance degrades significantly, enabling developers to take proactive action.
Types of system testing
With system testing, a QA team gauges if an application meets all its technical, business, and functional requirements. To accomplish this, the QA team might utilize various software testing techniques that determine the overall test coverage for an application and help catch critical defects that hamper an application’s core functionalities before release.
The following are the common types of system testing techniques:
- Performance testing. It measures the system’s speed, average load time, stability, reliability, and peak response team under various conditions. It typically involves stress testing and may include hardware and software testing tools.
- Usability testing. These tests evaluate if a system is easy to use and functional for the end user. Metrics, including user error rates, task success rates, the time it takes a user to complete a task, and user satisfaction, are used during testing.
- Load testing. This tests system or software performance under real-life extreme load and test scenarios. Metrics, such as throughput, number of users, and latency, are measured through this testing.
- Regression testing. Also known as sanity testing, it ensures that all changes introduced into an application or code during system testing, recent code changes, or updates haven’t caused any new bugs or issues. Regression testing is responsible for the functionality of the existing features of a system or software.
- Migration testing. This is conducted to ensure the smooth migration of legacy systems to new systems without disruptions, data loss, or downtimes.
- Scalability testing. This measures an application’s or system’s capability to scale up or down when meeting the changing user requirements.
- Functionality testing. This is conducted to validate a system’s functionality against its functional and business requirements.
- Recovery testing. This type of non-functional testing ensures that a system can recover from specific system errors, crashes, and failures.
Phases of system testing
System testing examines every application component to ensure that it works as a complete and unified whole. A QA team typically conducts system testing after it checks individual modules with functional or user story testing and then each component through integration testing.
If a software build achieves the desired results in system testing, it gets a final check via acceptance testing before it goes to production, where users consume the software. An app dev team logs all defects and establishes tolerable kinds and numbers.
Typically, system testing goes through the following stages:
- Test environment. In this initial stage, a test server is set up to create a testing environment, enabling a tester to run a set of predefined test cases and test scripts.
- Test case. This stage generates the test case for the testing process.
- Test data. At this stage, the data to be tested is generated.
- Test case execution. Test cases are executed once the test case and test data are generated.
- Reporting of defects. This is the stage where defects in the system are identified.
- Regression testing. This is done to see if the previous stages introduced any problems into the development process.
- Defect logging. All the identified defects are fixed at this stage.
- Retest. A test is repeated if it’s unsuccessful.
In this Software Testing Tutorial, we will learn about what is system testing with examples. In the system testing phase fully integrated application is available for testing team to test. Testers test the complete system with system level test cases.
