1. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 1 Process Improvement u Understanding, Modelling and Improving the Software Process

2. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 2 u Understanding existing processes u Introducing process changes to achieve organisational objectives which are usually focused on quality improvement, cost reduction and schedule acceleration u Most process improvement work so far has focused on defect reduction. Reflects increasing attention paid by industry to quality Process improvement

3. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 3 u Process analysis Model and analyse (quantitatively if possible) existing processes u Improvement identification Identify quality, cost or schedule bottlenecks u Process change introduction Modify the process to remove identified bottlenecks u Process change training Train staff involved in new process proposals u Change tuning Evolve and improve process improvements Process improvement stages

4. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 4 The process improvement process

5. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 5 u Process quality and product quality are closely related u A good process is usually required to produce a good product Process and product quality

6. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 6 Principal product quality factors

7. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 7 u Study an existing process to understand its activities u Produce an abstract model of the process. You should normally represent this graphically. Several different views (e.g. activities, deliverables, etc.) may be required u Analyse the model to discover process problems. Involves discussing activities with stakeholders Process analysis and modelling

8. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 8 u Activities Has clearly defined objective, entry and exit conditions. Often carried out by a single person. u Processes Set of activities with some coherence and an agreed objective. u Deliverables Tangible output of an activity. Usually a document. u Conditions Predicate which must hold either before or after a process or activity. Software process model elements

9. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 9 u Roles A bounded area of responsibility. Examples are configuration manager, test engineer, etc. u Exceptions An event which requires some special handling and is not processed by normal activities. Usually handled as they arise without a pre-planned strategy. Software process model elements

10. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 10 u Wherever possible, quantitative process data should be collected However, where organisations do not have clearly defined process standards this is very difficult as you don’t know what to measure. A process may have to be defined before any measurement is possible u Process measurements should be used to assess process improvements But this does not mean that measurements should drive the improvements. The improvement driver should be the organizational objectives Process measurement

11. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 11 u Time taken for process activities to be completed E.g. Calendar time or effort to complete an activity or process u Resources required for processes or activities E.g. Total effort in person-days u Number of occurrences of a particular event E.g. Number of defects discovered Classes of process measurement

12. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 12 u Goals What is the organisation trying to achieve? The objective of process improvement is to satisfy these goals u Questions Questions about areas of uncertainty related to the goals. You need process knowledge to derive these u Metrics Measurements to be collected to answer the questions Goal-Question-Metric Paradigm

13. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 13 ISO 9000 u Document what are you doing u Do what you have documented to do u You must have a set of documents describing Organization Documentation Management (similar to configuration management) Development and maintenance process infrastructure support u ISO 9000 certification

14. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 14 ISO 9000 u Can be applied on any type of organization u ISO-9000-3 - is ISO 9000 for the software production Specific issues for software development and maintenance

15. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 15 u Capability Maturity Model u US Defense Dept. funded institute associated with Carnegie Mellon -Software engineering Institute (SEI) u Mission is to promote software technology transfer particularly to defense contractors u Maturity model proposed in mid-1980s, refined in early 1990s. CMM - Process model

16. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 16 The SEI process maturity model

17. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 17 u Initial Essentially uncontrolled u Repeatable Product management procedures defined and used u Defined Process management procedures and strategies defined and used u Managed Quality management strategies defined and used u Optimising Process improvement strategies defined and used Maturity model levels

18. Key process areas ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31. Slide ##

19. Key process areas - level 2 Initial ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31. Slide ## Software Configuration Management Software Quality Assurance Software project planning Requirements management Software Project tracing and oversight Software subcontract management

20. Key process areas - main characteristics Software configuration management Software quality assurance Software subcontract management Software project tracking and oversight Software project planning Requirements management Initial Repeatable Managed Optimizing ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31. Slide ## Peer reviews Training program Organization process focus Software quality management Process change management Technology change management

21. ©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31 Slide 21 u Focuses on project management rather than product development. u Ignores use of technologies such as rapid prototyping. u Does not incorporate risk analysis as a key process area u No marketing issues SEI model problems