Non-functional requirements analysis modeling for software product lines

In most IT projects, software developers usually pay attention to functional requirements that satisfy business needs of the system. Non-functional requirements (NFR) such as performance, usability, security, etc. are usually handled ad-hoc during the system testing phase, when it is late and costly to fix problems. Due to the importance and criticality of NFR, the author study the problem of modeling NFR for software product lines (SPL), which adds yet an additional dimension of complexity. This paper will survey the software engineering literature, in search of a systematic way to analyze and design NFR, from the perspectives of the concept of commonality and variability of SPL and the characteristics of NFR. Finally, the author proposes a methodology based on the extension of product line UML-based software engineering (PLUS) techniques, for a unified and automated method to model NFR throughout all phases of SPL engineering.