Lec 07, 09.pdf

Processes and Process Models Lec 07, 09 1  Process - 1 A process is an organized set of activities, which transforms inputs to outputs We can use synonyms of process such as: procedure, method, course of action, etc. Processes are...

Processes and Process Models Lec 07, 09 1  Process - 1 A process is an organized set of activities, which transforms inputs to outputs We can use synonyms of process such as: procedure, method, course of action, etc. Processes are essential for dealing with complexity in real world 2  Process - 2 Processes document the steps in solving a certain problem They allow knowledge to be reused They Allow people to apply the process in their similar problems 3  Examples of Processes - 1 An instruction manual for operating a ATM machine. An instruction manual for assembling a computer or its parts A procedure manual for operating a motor vehicle radio and CD player 4  Examples of Processes - 2 A quality manual for software development. Such a manual describes the processes, which should be used to assure the quality of the software 5  Software Processes Software engineering, as a discipline, has many processes These processes help in performing different software engineering activities in an organized manner 6  Software Processes Requires creativity Provides interactions between a wide range of different people Helps in engineering judgment Requires background knowledge 7 Examples of Software Processes Software engineering development process (SDLC) Requirements engineering process Design process Quality assurance process Change management process 8 Software Requirements Engineering Process Before discussing different aspects of requirements engineering process, let us discuss the concept of process models 9  Process Models A process model is a simplified description of a process presented from a particular perspective There may be several different models of the same process No single model gives a complete understanding of the process being modeled 10  Context of RE Process in Waterfall Model System requirements engineering Software Design Implementatio n Verification/ System testing Maintenance 11 Another Perspective on Context of RE Process System acquisition Requirements engineering System design 12  Activity Model of the Requirements Engineering Process Requirements Requirements Requirements Requirements Elicitation Analysis and Specification Validation Negotiation User Needs, Domain Information, Agreed Existing System Requirements Requirements Information, Regulations, Document Standards, Etc. 13  Spiral Model of RE Process Informal statement of requirements Requirement Requirement analysis elicitation and negotiation Requirements START Agreed document and requirements validation report Requirement Requirement documentation validation Draft requirements document 14  Summary A process is an organized set of activities which transforms inputs to outputs, and they help in coping with complexity in the world Differences between these processes usually emerge at the level of detailed description A process model is a simplified description of a process presented from a particular perspective 15  References ‘Requirements Engineering: Processes and Techniques’ by G. Kotonya and I. Sommerville, John Wiley & Sons, 1998 16