Quality Models for Free/Libre Open Source Software Towards the “Silver Bullet”?

Selecting the right software is of crucial importance for businesses. Free/Libre Open Source Software (FLOSS) quality models can ease this decision-making. This paper introduces a distinction between first and second generation quality models. The former are based on relatively few metrics, require deep insights into the assessed software, relying strongly on subjective human perception and manual labour. Second generation quality models strive to replace the human factor by relying on tools and a multitude of metrics. The key question this paper addresses is whether the emerging FLOSS quality models provide the “silver bullet” overcoming the shortcomings of first generation models. In order to answer this question, OpenBRR, a first generation quality model, and QualOSS, a second generation quality model, are used for a comparative assessment of Asterisk, a FLOSS implementation of a telephone private branch exchange. Results indicate significant progress, but apparently the “silver bullet” has not yet been found.