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4 Chapter 4: Beginning the Analysis: Investigating System Requirements Systems Analysis and Design in a Changing World, 3 rd Edition 4 Systems Analysis and Design in a Changing World, 3rd Edition 2 Learning Objectives ◆ Describe the activities of the systems analysis life cycle phase ◆ Explain the effect of business process reengineering on activities of the analysis phase ◆ Describe the difference between functional and nonfunctional system requirements ◆ Identify and understand the different types of users who will be involved in investigating system requirements 4 Systems Analysis and Design in a Changing World, 3rd Edition 3 Learning Objectives (continued) ◆ Describe the kind of information that is required to develop system requirements ◆ Determine system requirements through review of documentation, interviews, observation, prototypes, questionnaires, vendor research, and joint application design sessions ◆ Discuss the need for validation of system requirements to ensure accuracy and completeness and the use of a structured walkthrough 4 Systems Analysis and Design in a Changing World, 3rd Edition 4 Overview ◆ Analysis phase of SDLC skills needed: ● Fact-finding for investigation of system requirements ● Analyst should learn details of business processes and daily operations ● Analyst should become as knowledgeable as business domain users to build credibility ● Analyst brings fresh perspective to problem ● Modeling of business processes based on system requirements 4 Systems Analysis and Design in a Changing World, 3rd Edition 5 The Analysis Phase in More Detail ◆ Gather information ◆ Define system requirements ● Logical model and physical model ◆ Prioritize requirements ◆ Prototype for feasibility and discovery ◆ Generate and evaluate alternatives ◆ Review recommendations with management 4 Systems Analysis and Design in a Changing World, 3rd Edition 6 The Activities of the Analysis Phase 4 Systems Analysis and Design in a Changing World, 3rd Edition 7 Activities of the Analysis Phase and Their Key Questions 4 Systems Analysis and Design in a Changing World, 3rd Edition 8 Business Process Reengineering and Analysis ◆ Fundamental strategic approach to organizing company ◆ Streamlines internal processes to be as efficient and effective as possible ◆ Questions basic assumptions for doing business and seeks to find a better way ◆ Uses IT as BPR enabler ◆ Systems analyst may discover opportunities for process improvement ◆ Any project may include components of BPR 4 Systems Analysis and Design in a Changing World, 3rd Edition 9 System Requirements ◆ New system capabilities and constraints ◆ Functional requirements are: ● Activities system must perform ● Based on procedures and business functions ● Documented in analysis models ◆ Nonfunctional requirements include: ● Operating environment or performance objectives ● Usability, reliability, and security requirements 4 Systems Analysis and Design in a Changing World, 3rd Edition 10 Stakeholders – The Source of System Requirements ◆ People with interest in successful system implementation ◆ Three primary groups of stakeholders: ● Users (use system) ● Clients (pay for and own system) ● Technical staff (ensure system operation) ◆ Every type of stakeholder is identified by analyst [...]... to system 12 4 Techniques for Information Gathering x Analysis phase done to understand business functions and develop system requirements x Original structured approach q q x Create model of existing system Derive requirements from existing system model Current approach q Identify logical requirements for new system q Balance the review of current business functions with new system requirements 13 4. .. for system quality q System analyst, project manager are partners 34 4 Summary x Analysis Phase Activities q q Define system requirements q Prioritize requirements q Prototype for feasibility and discovery q Generate and evaluate alternatives q x Gather information Review recommendations with management BPR is becoming widespread and can affect analysis phase 35 4 Summary (continued) x Gathering system. .. Vendor Research x Technical specifications from vendor x Demo or trial system x References of existing clients x On-site visits x Printout of screens and reports 33 4 Validating the Requirements x Make sure gathered information is correct x Structured walkthrough q q Verify and validate system requirements q x Effective means of implementing quality control early in project Review of findings from investigation... Identify logical requirements for new system q Balance the review of current business functions with new system requirements 13 4 Information Gathering and Model Building 14 Themes for Information-Gathering Questions 4 15 4 Fact Finding Methods x Review existing reports, forms, and procedure descriptions x Interview and discussion processes with users x Observe and document business processes x Build... Interviews 20 4 A Sample Open-items List 21 4 Observe and Document Business Processes x Varies from office walkthrough to performing actual tasks x Not necessary to observe all processes at same level of detail x May make users nervous, so use common sense x May be documented with workflow (activity) diagrams 22 4 Activity Diagram Symbols 23 Simple Activity Diagram to Demonstrate a Workflow 4 24 4 Activity... support (Laptops) q CASE Tools q Group support systems (GSS) 30 4 A JAD Facility 31 4 Research Vendor Solutions x Many problems have been solved by other companies x Positive contributions of vendor solutions q q May be state of the art q x Frequently provide new ideas Cheaper and less risky Danger q May purchase solution before understanding problem 32 4 Useful Techniques in Vendor Research x Technical... affect analysis phase 35 4 Summary (continued) x Gathering system requirements q q x Functional and Nonfunctional Work with various stakeholders (users, clients, technical staff) “What kind of information do I need?” q What are the business processes and operations? q How are the business processes performed? q What are the information requirements? 36 ... large number of stakeholders x Preliminary insight into business x Not well suited for gathering detailed information x Closed-ended questions direct person answering question x Open-ended questions encourage discussion and elaboration 27 4 Conduct Joint Application Design Sessions x Expedite investigation of systems requirements x Seeks to compress fact-finding, modeling, policy formation, and verification... all important stakeholders present 28 4 Joint Application Design Participants x Session leader trained in group dynamics and JAD group facilitation x Knowledgeable business and system users x Policy making managers x Technical staff representatives to handle: q q Operating environments q x Computer and network configurations Security issues Project team members 29 4 Joint Application Design Facilities... guide interviews 17 4 Sample Order Form for RMO 18 4 Conduct Interviews and Discussions with Users x Effective way to understand business functions and rules x Time-consuming and resource-expensive x May require multiple sessions to: q Meet all users q Understand all processing requirements x Can meet with individuals or groups of users x List of detailed questions prepared 19 4 Sample Checklist to . 4 Chapter 4: Beginning the Analysis: Investigating System Requirements Systems Analysis and Design in a Changing World, 3 rd Edition 4 Systems Analysis and Design in. Edition 6 The Activities of the Analysis Phase 4 Systems Analysis and Design in a Changing World, 3rd Edition 7 Activities of the Analysis Phase and Their Key Questions 4 Systems Analysis. processes based on system requirements 4 Systems Analysis and Design in a Changing World, 3rd Edition 5 The Analysis Phase in More Detail ◆ Gather information ◆ Define system requirements ● Logical