Abstract
Because the complexity of today's systems is so high, the changes in technology so fast, and the use of technology so broad, systems are no longer defined and bounded by their physical form, nor by their components. Instead, systems are defined by the characteristics of their use. The traditional performance focus, black-box system testing is no longer adequate to evaluate the capability and dependability of today's complex systems. This paper presents five system test objectives for today's systems, a usage-model approach to determine the system application environments as well as to verify functional aspects of the systems, and a structure testing technique to explore the non-functional aspects of the systems.