Existing field data from similar systems or simulation and estimation make these estimates possible. As will be discussed later, system usage data collection software should be built into the overall system logic. Before discussing test case preparation, let us examine some testing terminology. Test cases, on the other hand, incorporate all the independent aspects of the run but are independent of environment. Thus, a test case can be used for multiple test runs.
Runs involve test cases executing in operational modes, driven by test procedures.
The test procedure is the statistical specification of the set of runs associated with an operational mode, made by providing values of operation occurrence rates. The relationship among these terms is best illustrated in Figure 2. Test Cases, Operational Modes, and Runs. The area represents all possible runs for the program, each of which is represented by a point. However, the runs are different because the operational modes are different, resulting in different environments.