Lero© 2010 Software Process & Quality Improvement Dr. Ita Richardson Lero – the Irish Software Engineering Research Centre and Department of Computer Science & Information Systems University of Limerick 1 Lero© 2010

LECTURE 2: SOFTWARE PROCESSES

Lero© 2010 Software Process “Set of activities, methods, practices and transformations that people use to develop and maintain software and the associated products” Paulk et al., 1993

Lero© 2010 Software Process Organisation Customer interaction Supplier interaction Development Project Management Risk Management Support activities

Lero© 2010 Total Quality Management Improved Manufacturing Process Improved Manufactured Product

Lero© 2010 Software Process Improved software process Improved software product ?

Lero© 2010 SOFTWARE PROCESS MODELS

Lero© 2010 Software Process Models Capability Maturity Model SPICE - ISO15504 ISO9001 / ISO9000-3

Lero© 2010 Capability Maturity Model Integrated Based on Crosby’s Maturity Grid Level 1 - Initial Level 2 - Repeatable Level 3 - Defined Level 4 - Managed Level 5 – Optimizing – Chrissis et al. 2003

Lero© 2010 SPICE – ISO15504 Framework – Architecture for processes associated with software process – Set of criteria for performing assessments – Tool support for assessment

Lero© 2010 Process Categories Customer-supplier process Engineering process Project process Support process Organisation process

Lero© 2010 SPICE Capability levels 0 Not-Performed – General failure to perform base practices 1 Performed-Informally 2 Planned-and-Tracked 3 Well-Defined 4 Quantitatively-Controlled 5 Continuously-Improving

Lero© 2010 IMPROVING SOFTWARE PROCESS

Lero© 2010 Roots of Software Process Improvement U.S. Department of Defence Software Engineering Institute at Carnegie- Mellon University Watts S. Humphrey, 1989 Capability Maturity Model

Lero© 2010 Software Process Improvement Increase in Productivity Reduction in Defects Reduction in Error Rates Decrease in Costs Increase in On-Time Deliverables Reduction in Rework Savings in Test Time

Lero© 2010 Process in an organisation Investigate what is wrong with the process? Suggest improvements to be made

Lero© 2010 Continuous Improvement Plan - Do - Check - Act

Lero© 2010 What is a Process? “Sequence of steps performed for a given purpose” IEEE-STD-610 “Set of activities, methods, practices and transformations that people use to develop and maintain software and the associated products” Paulk et al., 1993

Lero© 2010 Some processes Develop software design Perform configuration management Manage the project Provide skilled human resources

Lero© 2010 Software Process Improvement Proponents of Software Process Improvement state that the product is improved when the process is improved

Lero© 2010 Argument for ….. …“the link between the quality of the development process and the final product is well established” Gillies, 1992 “It is now generally recognized that an effective way to improve software quality is by improving the development and maintenance process” Humphrey, 1996

Lero© 2010 Argument against "there is, as yet, no convincing evidence that higher rated companies produce better quality software" Fenton et al., 1995

Lero© 2010 Research Conclusions “Improving the process improves the quality of the product; it also improves implementation and maintenance of the product” “…many of the changes which happened as a result of this project were moving the researched companies out of chaos”

Lero© 2010 Software Problems Business importance of software is increasing – Increasing number of services are available to organisations Poor software quality – Is expensive – Reduces customer satisfaction – Delayed shipments – Expensive service / enhancement

Lero© 2010 Acknowledgements The information presented in these slides has been collected from a variety of sources including: – Software Quality Assurance: From Theory to Implementation by Daniel Galin, 2003 – Software Process Improvement: Practical Guidelines for Business Success by Sami Zahran, 1998 – Research carried out by post-doctoral researchers and PhD students at Lero – the Irish Software Engineering Research Centre, Ireland under the supervision of Dr. Ita Richardson – Software Process: Improvement and Practice (journal) – The SPIRE Handbook: Better, Faster, Cheaper Software Development in Small Organisations, edited by Marty Sanders (Version 1, 1998) and Jill Pritchet (Version 2, 2000) The research presented in this lecture has been partially supported by Science Foundation Ireland funded through Global Software Development in SMEs Cluster Grant (no 03/IN3/1408C) and Lero – the Irish Software Engineering Research Centre (CSET grant no 03CE2/I303.1).

Lero© 2010 References Paulk Mark C., Bill Curtis, Mary Beth Chrissis, Charles V Weber, "The Capability Maturity Model for Software, Version 1.1", Technical Report SEI- 93-TR-24, Software Engineering Institute, Carnegie Mellon University, U.S.A., 1993 Chrissis, Mary Beth, Mike Konrad, Sandy Shrum, CMMI – Guidelines for Process Integration & Product Improvement, SEI Series in Software Engineering, Addison-Wesley 2003 –,, © S-Cube – 26/