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Requirements Determination.Systems analysis and design, 6th.edition.Dennis, wixom, and roth.Roberta M. Roth © 2015 John Wiley & Sons. All Rights 1Learning Objectivesq Explain the analysis phase of the SDLCq Describe the content and purpose of the requirements definition. statementq Classify requirements correctly as business, user, functional, or. nonfunctional requirementsq Employ the requirement elicitation techniques of interviews, JAD. sessions, questionnaires, document analysis, and observationq Define the role that each requirement elicitation technique plays in. determining requirementsq Describe several analysis strategies that can help the analyst. discover requirements © 2015 John Wiley & Sons. All Rights 2The Analysis Phase.Determining what the new system should do. © 2015 John Wiley & Sons. All Rights 3Overview of the Analysis Phaseq Goal is to develop a clear understanding of the new. system’s requirements. o Understand the “As-Is” system. o Identify Improvements. o Develop the “To-Be” system concept.q Use critical thinking skills to determine the true. causes of problems.q Apply knowledge of IS and business to outline. ways to solve the problems in the new system. © 2015 John Wiley & Sons. All Rights 4Requirements Determination.Understanding requirements. © 2015 John Wiley & Sons. All Rights 5What is a Requirement?q A statement of what the system must do; or.q A statement of characteristics the system must. have.q Types of requirements:. o what the business needs (business requirements);. o what the users need to do (user requirements);. o what the software should do (functional requirements);. o characteristics the system should have (nonfunctional. requirements); and. o how the system John Wiley be built Rights. © 2015 should & Sons. All (system requirements) 6User Requirementsq What the user needs to do to complete a needed. job or task.q Focus on user tasks that are integral to business. operations.q Understanding user tasks helps reveal ways that. the new system can support those tasks © 2015 John Wiley & Sons. All Rights 7Functional Requirementsq A process the system should perform as a part of. supporting a user task, or.q Information the system should provide as the user. performs a task.q Specify the support the system will provide to the. user in fulfilling his/her work tasks © 2015 John Wiley & Sons. All Rights 8More on.Functional.Requireme.nts.o Process-oriented.o Information-oriented. © 2015 John Wiley & Sons. All Rights 9Nonfunctional Requirementsq Behavioral properties the system must have. o Operational – physical and technical operating environment. o Performance – speed, capacity, and reliability needs. o Security – access restrictions, needed safeguards. o Cultural and political – issues that will affect the final system.q Nonfunctional requirements are discussed in. Chapter 8 (Architecture Design) © 2015 John Wiley & Sons. All Rights 10More on.Nonfunctio.nal.Requireme.o Behavioral properties.ntssystem must have. the. © 2015 John Wiley & Sons. All Rights 11Documenting Requirementsq Requirements definition report. o Text document listing requirements in outline form. o Organized in logical groupings. o Priorities may be included.q Key purpose is to define the project scope. o what is included. o what is not included © 2015 John Wiley & Sons. All Rights 12Requirements Elicitation Techniques.Ways to discover requirements. © 2015 John Wiley & Sons. All Rights 13Requirements Elicitation in Practiceq Use every interaction with managers