Lecture Chapter 4: Beginning the analysis - Investigating system requirements

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Lecture "Chapter 4: Beginning the analysis - Investigating system requirements" provides students with the knowledge: The analysis phase in more detail, system requirements, techniques for Information gathering, conduct interviews and discussions with users, activity diagram showing concurrent paths,... Invite you to consult.

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Nội dung Text: Lecture Chapter 4: Beginning the analysis - Investigating system requirements

4 4 Learning Objectives Chapter 4:  Describe the activities of the systems analysis life Beginning the Analysis: cycle phase Investigating System Requirements  Explain the effect of business process reengineering on activities of the analysis phase Systems Analysis and Design in a Changing  Describe the difference between functional and World, 3rd Edition nonfunctional system requirements  Identify and understand the different types of users who will be involved in investigating system requirements Systems Analysis and Design in a Changing World, 3rd Edition 2 4 4 Learning Objectives (continued) Overview  Describe the kind of information that is required  Analysis phase of SDLC skills needed: to develop system requirements  Fact-finding for investigation of system requirements  Determine system requirements through review of documentation, interviews, observation,  Analyst should learn details of business processes prototypes, questionnaires, vendor research, and and daily operations joint application design sessions  Analyst should become as knowledgeable as business domain users to build credibility  Discuss the need for validation of system requirements to ensure accuracy and  Analyst brings fresh perspective to problem completeness and the use of a structured  Modeling of business processes based on system walkthrough requirements Systems Analysis and Design in a Changing World, 3rd Edition 3 Systems Analysis and Design in a Changing World, 3rd Edition 4 4 4 The Analysis Phase in More Detail The Activities of the Analysis Phase  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 Systems Analysis and Design in a Changing World, 3rd Edition 5 Systems Analysis and Design in a Changing World, 3rd Edition 6
4 4 Activities of the Analysis Phase Business Process Reengineering and Their Key Questions 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 Systems Analysis and Design in a Changing World, 3rd Edition 7 Systems Analysis and Design in a Changing World, 3rd Edition 8 4 4 Stakeholders – The Source of System Requirements System Requirements  New system capabilities and constraints  People with interest in successful system  Functional requirements are: implementation  Activities system must perform  Three primary groups of stakeholders:  Based on procedures and business functions  Users (use system)  Documented in analysis models  Clients (pay for and own system)  Nonfunctional requirements include:  Technical staff (ensure system operation)  Operating environment or performance objectives  Usability, reliability, and security requirements  Every type of stakeholder is identified by analyst Systems Analysis and Design in a Changing World, 3rd Edition 9 Systems Analysis and Design in a Changing World, 3rd Edition 10 4 4 Stakeholders Interested Users as Stakeholders in New System Development  Horizontal user roles - information flow across departments  Vertical user roles - information needs of clerical staff, middle management, and senior executives  Business users perform day-to-day operations  Information users need current information  Management users need summary information  Executive users need strategic information  External users may have access to system Systems Analysis and Design in a Changing World, 3rd Edition 11 Systems Analysis and Design in a Changing World, 3rd Edition 12
4 4 Techniques for Information Gathering Information Gathering and Model Building  Analysis phase done to understand business functions and develop system requirements  Original structured approach  Create model of existing system  Derive requirements from existing system model  Current approach  Identify logical requirements for new system  Balance the review of current business functions with new system requirements Systems Analysis and Design in a Changing World, 3rd Edition 13 Systems Analysis and Design in a Changing World, 3rd Edition 14 4 4 Themes for Information-Gathering Fact Finding Methods Questions  Review existing reports, forms, and procedure descriptions  Interview and discussion processes with users  Observe and document business processes  Build prototypes  Distribute and collect questionnaires  Conduct joint application design (JAD) sessions  Research vendor solutions Systems Analysis and Design in a Changing World, 3rd Edition 15 Systems Analysis and Design in a Changing World, 3rd Edition 16 4 4 Review Existing Reports, Forms, Sample Order Form for RMO and Procedure Descriptions  Source: External industry wide professional organizations and trade publications  Source: Existing business documents and procedure descriptions within organization  Identify business rules, discrepancies, and redundancies  Be cautious of outdated material  Obtain preliminary understanding of processes  Use as guidelines / visual cues to guide interviews Systems Analysis and Design in a Changing World, 3rd Edition 17 Systems Analysis and Design in a Changing World, 3rd Edition 18
4 4 Conduct Interviews and Discussions with Users Sample Checklist to Prepare for User Interviews  Effective way to understand business functions and rules  Time-consuming and resource-expensive  May require multiple sessions to:  Meet all users  Understand all processing requirements  Can meet with individuals or groups of users  List of detailed questions prepared Systems Analysis and Design in a Changing World, 3rd Edition 19 Systems Analysis and Design in a Changing World, 3rd Edition 20 4 4 A Sample Open-items List Observe and Document Business Processes  Varies from office walkthrough to performing actual tasks  Not necessary to observe all processes at same level of detail  May make users nervous, so use common sense  May be documented with workflow (activity) diagrams Systems Analysis and Design in a Changing World, 3rd Edition 21 Systems Analysis and Design in a Changing World, 3rd Edition 22 4 4 Activity Diagram Symbols Simple Activity Diagram to Demonstrate a Workflow Systems Analysis and Design in a Changing World, 3rd Edition 23 Systems Analysis and Design in a Changing World, 3rd Edition 24
4 4 Activity Diagram Showing Concurrent Paths Build Prototypes  Preliminary working model of a larger, more complex system  Discovery, design, evolving prototypes  Operative  Working model to provide “look and feel”  Focused to accomplish single objective  Quick  Built and modified rapidly with CASE tools Systems Analysis and Design in a Changing World, 3rd Edition 25 Systems Analysis and Design in a Changing World, 3rd Edition 26 4 4 Distribute and Collect Questionnaires Conduct Joint Application Design Sessions  Limited and specific information from a large  Expedite investigation of systems requirements number of stakeholders  Preliminary insight into business  Seeks to compress fact-finding, modeling, policy  Not well suited for gathering detailed information formation, and verification activities into shorter time frame  Closed-ended questions direct person answering question  Critical factor is to have all important  Open-ended questions encourage discussion and stakeholders present elaboration Systems Analysis and Design in a Changing World, 3rd Edition 27 Systems Analysis and Design in a Changing World, 3rd Edition 28 4 4 Joint Application Design Participants Joint Application Design Facilities  Session leader trained in group dynamics and  Conducted in special room JAD group facilitation  Limit interruptions  Knowledgeable business and system users  May be off-site  Policy making managers  Resources  Technical staff representatives to handle:  Overhead projector, white board, flip charts, work  Computer and network configurations material  Operating environments  Electronic support (Laptops)  Security issues  CASE Tools  Project team members  Group support systems (GSS) Systems Analysis and Design in a Changing World, 3rd Edition 29 Systems Analysis and Design in a Changing World, 3rd Edition 30
4 4 A JAD Facility Research Vendor Solutions  Many problems have been solved by other companies  Positive contributions of vendor solutions  Frequently provide new ideas  May be state of the art  Cheaper and less risky  Danger  May purchase solution before understanding problem Systems Analysis and Design in a Changing World, 3rd Edition 31 Systems Analysis and Design in a Changing World, 3rd Edition 32 4 4 Useful Techniques in Vendor Research Validating the Requirements  Technical specifications from vendor  Make sure gathered information is correct  Structured walkthrough  Demo or trial system  Effective means of implementing quality control early in project  References of existing clients  Verify and validate system requirements  Review of findings from investigation and of  On-site visits models based on findings  Project manager responsible for system quality  Printout of screens and reports  System analyst, project manager are partners Systems Analysis and Design in a Changing World, 3rd Edition 33 Systems Analysis and Design in a Changing World, 3rd Edition 34 4 4 Summary Summary (continued)  Analysis Phase Activities  Gathering system requirements  Gather information  Functional and Nonfunctional  Define system requirements  Work with various stakeholders (users, clients,  Prioritize requirements technical staff)  Prototype for feasibility and discovery  “What kind of information do I need?”  Generate and evaluate alternatives  What are the business processes and operations?  Review recommendations with management  How are the business processes performed?  BPR is becoming widespread and can affect  What are the information requirements? analysis phase Systems Analysis and Design in a Changing World, 3rd Edition 35 Systems Analysis and Design in a Changing World, 3rd Edition 36
4 Summary (continued)  Primary information gathering techniques  Review existing reports, forms, and procedure descriptions  Conduct interviews and discussions with users  Observe and document business processes  Build prototype working models  Distribute and collect questionnaires  Conduct JAD sessions  Research vendor solutions Systems Analysis and Design in a Changing World, 3rd Edition 37