Technology – Integration Testing Vs. System Testing

Software applications may contain several different modules, which essentially require a partnership between teams during the development process. The individually developed modules get integrated to form a ready-to-use software application. But before the software gets released to the market, it must be thoroughly tested to ensure it meets user requirement specifications.

Integration Testing

The integration testing phase involves assembling and combining the modules tested separately. It helps detect defects in the interfaces during the early stages and ensure the software components work as one unit.

Integration testing has two puposes: component and system integration testing.

  • Component integration testing: With this level of testing, it deals explicitly with the interactions between the software components tested separately.
  • System integration testing: It focuses on evaluating the interactions between various types of systems or micro-services.

System Testing

System testing is the most expansive level of software testing. It mainly involves:

  • Load testing: Determines the level of responsiveness and stability under real-life loads.
  • Usability testing: Determines the ease of use from the perspective of an end-user.
  • Functional testing: Ensures all the software features work as intended.
  • Security testing: Detects if there are any security flaws in the system that might lead to unauthorized access to data.
  • Recovery testing: Determines the possibility of recovery if the system crashes.
  • Regression testing: Confirms the software application changes have not negatively affected the existing features.
  • Migration testing; Ensures the software allows for seamless migration from old infrastructure systems to new ones when necessary.

Main Differences between Integration Testing and System Testing

Integration testing

  • Performed after modules (units) of the software have been tested separately.
  • It checks the interface modules.
  • Limited to functional testing.
  • Testers use the big bang, top-down, bottom-up, or sandwich/hybrid testing approaches.
  • Testers use a combination of white/grey box testing and black-box testing techniques.
  • Test cases mimic the interactions between modules.
  • Performed by independent developers or software developers themselves.

System testing

  • Performed after integration testing.
  • Checks the system as a whole to ensure it meets the end-user requirements.
  • It features both functional and non-functional test aspects.
  • Tests cover several areas, including usability, performance, security, scalability, and reliability.
  • Testers use black-box testing techniques.
  • Test cases mimic the real-life circumstances of a user.
  • Performed by test engineers.

There you have it!