As discussed in Chapter 1, VVT engineers often use the term “testing” colloquially to mean VVT. But, in a narrower sense, following the VVT definition, “testing” is a subset of verification and validation, dealing with actively operating the system and verifying or validating it. Accordingly, this chapter describes system VVT testing methods in the narrow sense. After the introduction, this chapter is divided into two main parts: white-box system testing and black-box system testing. The second part is further divided into (1) basic testing, (2) high-volume testing, (3) special testing, (4) environment testing and (5) phase testing. Each section describes relevant VVT methods.
The fundamental system testing process is depicted in Figure 5.1. System specifications, which include a list of system requirements and other important elements, are the very basis for the design and building of the target system. These are the “musts” and “shoulds” that dictate what the system must be and must do and for which the customer is willing to pay. These same system specifications are therefore the measure by which the system must be judged. Thus, system specifications are instrumental in generating the test cases needed to verify and validate the system. A test engineer or a group of test engineers then perform the specification-directed testing process and thus determine whether or not the system succeeds in meeting all of its specifications.