Quality of Service-Driven Requirements Analyses for Component Composition: A Two-Level Grammar++ Approach
Shih-Hsi Alex Liu, Fei Cao, Barrett R. Bryant, Jeff Gray, Rajeev R. Raje, Andrew M. Olson, Mikhail Auguston · Defense Technical Information Center (DTIC) · 2005
Component-based software engineering provides developers the opportunity to assemble entire systems from components. When applied to Distributed Real-Time and Embedded (DRE) systems, which components to assemble and how to assemble them are determined not only from functional correctness criteria but also assurance of the system's quality of service (QoS). This paper presents a grammatical QoS-driven approach to optimizing component assembly by reducing the search space of assembly alternatives through the elimination of infeasible components, with feasible components selected based on reasoning about nonfunctional requirements. The reasoning is realized through a rule engine with a knowledge base derived from the requirements phase of the software life cycle. In addition, the grammatical approach introduces well-defined semantics among the components being composed. The semantics assist in precisely and efficiently evaluating the individual component QoS, as well as system-wide QoS in a programmable fashion. The result is to facilitate straightforward and manageable component composition analyses from the perspective of QoS requirements.