Define test context and environment

As with each level of testing, the first step in performing System Acceptance Testing is to define what will be tested, the System Under Test (SUT). In order to verify and validate the entire system, the SUT encompasses the complete, deliverable system that includes both software and hardware. Acceptance tests frequently require a test bench to stimulate system’s hardware inputs and respond to its outputs. In addition, acceptance tests often require an environmental simulator that closes the loop between system outputs and inputs.

Define test cases

Acceptance test cases require fall into two categories: verification tests and validation test. Verification tests confirm that the product meets the requirements. Verify the system’s key capabilities. The concept of operations and system level use cases refine these capabilities. For each test case, define one or more test scripts so that exercise the capability. It is important to specify the scenario completely, including exception conditions. Acceptance testing generally requires that the customer, product manager, and quality assurance review and approve the test cases.

Validation tests show that the requirements the system was built from are correct. These test cases require the developer to think about how the product performs in its environment. Validation test cases frequently expose incorrect or incomplete requirement conditions. Therefore, these test cases should be identified as early in the development lifecycle as possible to reduce the propagation of the requirement defects.