What is the focus of system integration testing?

The focus of system integration testing is to assess the compatibility and interaction between different systems or components that have been integrated. During this phase, the primary objective is to ensure that the integrated system works as intended when various subsystems, services, or packages come together. This involves verifying that data is transmitted correctly between the components, that they communicate effectively, and that the combined functionalities meet the overall requirements.

This type of testing is crucial in identifying issues that may arise when different systems or modules are combined, which cannot be detected when testing components in isolation. It ensures that any dependencies and interactions between integrated parts are seamless and function harmoniously.

Options that center on the testing of individual components, performing stress tests, or conducting user acceptance testing focus on narrower aspects of software testing. Component testing evaluates discrete pieces in isolation, stress testing challenges the system under extreme conditions to assess its limits, and user acceptance testing involves validating the end product against user requirements. While all these testing types are important in their own contexts, they do not encapsulate the holistic verification of interacting systems that is the essence of system integration testing.