Alexis Kestler
Nothing frustrates users more than faulty, bug-ridden software. That‘s why testing is a critical phase of the standard software development lifecycle (SDLC). The goal of testing is to catch bugs and validate software quality before releasing it to customers.
Of all the testing types, system testing plays a vital role. It evaluates how well the fully integrated software works from end to end. Done right before launch, system testing can minimize post-deployment issues and instill confidence that the product will function as intended when it goes live.
This beginner‘s guide will explain what system testing is, why it matters, different test types, key phases, and examples. With this knowledge, you‘ll be better equipped to plan and perform effective system tests.
What Exactly is System Testing?
If you‘ve worked in software development, you‘ve likely heard terminology like unit testing, integration testing, system testing and user acceptance testing. These refer to different levels of testing applied as software components get built up into a complete product.
System testing sits at the higher levels, coming after integration testing and before UAT. At this stage, all software modules have already been unit tested and integrated together into one coherent system.
So in system testing, testers evaluate the completely integrated system as one entity. The focus is assessing how well the system meets functional and business requirements from an end-user perspective.
This involves testing in an environment configured to simulate real-world production settings. By mimicking real-use conditions, system testing can uncover defects and inconsistencies that unit and integration testing within development environments may miss.
In summary, system testing aims to validate software quality and reliability when operating as designed. The outcomes give stakeholders confidence that the system works properly before being deployed to customers.
Why Perform System Testing?
Some organizations wonder if system testing is necessary since software gets exposed to users eventually. While finding issues post-launch is one approach, it causes customer frustration and threatens brand reputation. Here are compelling reasons to conduct system testing pre-release:
Validate functionality – Test whether the integrated system operates all features properly from start to finish as per specifications.
Assess performance – Evaluate system speed, capacity, stability and resource usage under expected workloads.
Uncover hidden defects – Identify bugs, crashes, errors not caught earlier that could impact customer experience.
Improve security – Detect vulnerabilities and ensure system can withstand cyber attacks.
Enhance user experience – Check ease of use, navigation, compatibility and overall interaction quality.
Reduce failure risk – Minimize likelihood of issues arising when software goes live by testing rigorously first in a simulated environment.
In summary, system testing validates the software is truly ready for use as intended and identifies problems early so they can be fixed promptly. This prevents unhappy customers and expensive post-launch rework.
Types of System Testing
There are several flavors of system testing geared to assess different aspects:
Functional testing – Validate all features and functionality work correctly from end to end.
Performance testing – Check responsiveness, stability and speed under expected workloads.
Load testing – Assess behavior with varying user loads from low to peak levels.
Security testing – Identify vulnerabilities that could lead to cyber attacks.
Usability testing – Evaluate ease of use and navigation from an end-user perspective.
Regression testing – Verify recent code changes don‘t impact existing functionality.
Recovery testing – Check system robustness by simulating failures.
The right combination ensures well-rounded testing aligned to project priorities.
Key Phases in System Testing Process
Well-executed system testing follows a methodical sequence of steps:
1. Plan – Detail the scope, strategy, schedule, environment needs and resource requirements.
2. Design test cases – Define various use cases, scenarios and test data to validate system robustness.
3. Execute test cases – Run through test cases while monitoring system behavior compared to expected outcomes.
4. Log defects – Record and detail any failures, crashes or deviations from specifications.
5. Fix defects – Troubleshoot root causes then resolve bugs and issues.
6. Retest – Confirm fixes and new changes work properly without causing other functionality regressions.
7. Report – Summarize test results and remaining open defects or issues if any.
Repeating cycles systematically results in thorough validation status.
System Testing Example
To understand system testing better, let‘s walk through a simplified example for testing an e-commerce website:
Scope
The major website functions and user journeys targeted for system testing would include:
- User account registration and login
- Product browsing & search
- Adding items to shopping cart
- Checkout payment processing
- Order confirmation
- Site responsiveness with 500 concurrent users
Test Cases
Based on the scope, some sample high-level test cases include:
- Register as a new user with valid and invalid inputs into forms
- Check error validations on forms
- Search products using different keywords and filters
- Verify matching and accurate results displayed
- Add/remove various products to shopping cart
- Confirm cart quantity and total pricing updates correctly
- Checkout with test payment data
- Validate order confirmations received upon payment processing
- Access website concurrently with 500 virtual users
- Monitor site response times and error rates
Test Environments
The system test environment may utilize cloud infrastructure to simulate production scale. Popular tooling choices for test automation and monitoring include Selenium, JMeter, and New Relic.
Execution
With the test scope, cases and environments established, testers can run through these conditions while monitoring system behavior for deviations. Defects would get logged and prioritized for fixes afterwards.
Reporting
Consolidated reports would capture test coverage, defects found, resolutions implemented, and overall system stability. Stakeholders can then determine if the software is truly ready for release based on outcomes.
Key Takeaways
Here are main points to remember on system testing:
- It evaluates fully integrated software to uncover bugs before go-live.
- Various test types assess functionality, performance, security and usability.
- Following a methodical process is key to thorough validation.
- Outcomes determine software readiness for release to customers after fixes.
In summary, system testing plays a pivotal role by validating production readiness and reliability before deployment. Combining the right testing tools, infrastructure, data and processes leads to high quality outcomes.
