Software defect analysis of a multi-release telecommunications system

Abstract

This paper provides a study of several process metrics of an industrial large-scale embedded software system, the Lucent product Lambda-Unite™ MSS. This product is an evolutionary hardware/software system for the metropolitan and wide-area transmission and switching market. An analysis of defect data is performed, including and comparing all major (i.e. feature) releases till end of 2004. Several defect metrics on file-level are defined and analyzed, as basis for a defect prediction model. Main analysis results include the following. Faults and code size per file show only a weak correlation. Portion of faulty files per release tend to decrease across releases. Size and error-proneness in previous release alone is not a good predictor of a file's faults per release. Customer-found defects are strongly correlated with pre-delivery defects found per subsystem. These results are being compared to a recent similar study of fault distributions; the differences are significant. © Springer-Verlag Berlin Heidelberg 2005.