A New Software Metric to Complement Function Points: The Software Non-functional Assessment Process (SNAP)

Abstract : Sizing software requirements is an essential best practice in software project management for forecasting the work effort required for software development projects (and other related metrics). Arguably, the currently most accurate software metric for measuring the size of software is the International Function Point Users Group (IFPUG) function point, which has the ISO standard ISO/IEC 20926:2009. Function points basically measure the size of the data flow and storage through the software, which we define in this paper as functional requirements. But function points do not measure other software requirements, which also require work effort resources. IFPUG has recently completed a successful beta test of a new method to assess the size of other, nonfunctional requirements, which when used in conjunction with function points should further increase the accuracy of software forecasting. The authors believe that this Software Non-functional Assessment Process v. 2.0 (SNAP) is ready to enter industry and academia for initial practice and further research.