Presentation on theme: "Compare and contrast the terms ‘phases’, ‘steps’, ‘techniques’, and ‘deliverables’ as used in systems analysis & design."— Presentation transcript:
1Compare and contrast the terms ‘phases’, ‘steps’, ‘techniques’, and ‘deliverables’ as used in systems analysis & design.
2Phases are broad groupings of tasks Steps are tasks (work to be performed)Techniques are ways to carry out tasksDeliverables are the understanding (or materials) produced during task accomplishmentEach phase is itself composed of a series of steps, which rely upon techniques that produce deliverables (specific documents and files that provide understanding about the project).Example: When you apply for admission to a university, there are several phases that all students go through: information gathering, applying, and accepting. Each of these phases has steps—information gathering includes steps like searching for schools, requesting information, and reading brochures. Students then use techniques (e.g., Internet searching) that can be applied to steps (e.g., requesting information) to create deliverables (e.g., evaluations of different aspects of universities).
3Describe the major phases in the Systems Development Life Cycle (SDLC).
4Planning Analysis Design Implementation Justifying system; setting strategyAnalysisDeveloping logical specificationsDesignDeveloping physical specificationsImplementationConstructing (or installing), testing, converting, training, and providing support for system
5Describe the principal steps in the Planning Phase Describe the principal steps in the Planning Phase. What are the major deliverables?
6Project Initiation Project Management Deliverables: Identification of the system business valueProject ManagementWork, staffing, controls, and procedures definedDeliverables:System requestProblem statementBusiness case scenarioFeasibility analysisProject plan
7Describe the principal steps in the Analysis Phase Describe the principal steps in the Analysis Phase. What are the major deliverables?
8The analysis phase answers the questions of who will use the system, what the system will do, and where and when it will be used. During this phase, the project team investigates any current system(s), identifies improvement opportunities, and develops a concept for the new system. This phase has three steps:Analysis Strategy: Developed to guide the project team’s efforts. Such a strategy usually includes an analysis of the current system (as-is system) and its problems, and then ways to design a new system (to-be system).Requirements Gathering: The analysis of this information—in conjunction with input from project sponsor and many other people—leads to the development of a concept for a new system. The system concept is then used as a basis to develop a set of business analysis models that describes how the business will operate if the new system were developed.System Proposal: The analyses, system concept, and models are combined into a document called the system proposal, which is presented to the project sponsor and other key decision makers.
9Describe the principal steps in the Design Phase Describe the principal steps in the Design Phase. What are the major deliverables?
10Database and file specifications Program Design Design StrategyDetermining proper approach for acquiringSystem architectureDescribing basic hardware, software, and networkingUser interfaceDeveloping system’s overall structure, navigation, inputs, outputs, and screensDatabase and file specificationsSpecifying data storage structuresProgram DesignPlans and outlines for each program to be writtenDeliverable: System Specification
11Describe the principal steps in the Implementation Phase Describe the principal steps in the Implementation Phase. What are the major deliverables?
12Build system Train users Convert to new system Support new system Writing and testing systemTrain usersAssuring that end users understand new system's functions and work proceduresConvert to new systemManaging transition from old to newSupport new systemMonitoring performance of system and need for changesDeliverables: Programs, manuals, training materials, and plans for system support
13What are the roles of a project sponsor and the approval committee?
14Project sponsor Approval committee represents interests of business area that needs systemsubmits original system requestworks with development team to plan project scopeApproval committeeoversees activities of IS departmentidentifies and prioritizes systems projectsreceives periodic reports on projects' progress and determines if continued work is warranted
15What does "gradual refinement" mean in the context of SDLC?
16Initially, requirements are only vaguely understood Understanding is improved during Analysis phaseFurther detail is developed during DesignUnderstanding is fully expressed during Implementation
17Compare and contrast process-centered methodologies, data-centered methodologies, and object-oriented methodologies.
18Process-centered approaches emphasize transformation of data, which are secondary Data-centered approaches consider data to be primary, stable aspect of systemObject-oriented methodologies place a balanced emphasis on processes and dataArchitecture centricUse case drivenIncremental and iterative
19Compare and contrast Structured Design methodologies in general to RAD methodologies in general.
20Structured Design Methodologies: Fairly formal, step-by-step approachesProject moves through phases in systematic wayEmphasis on development of paper-based specificationsRAD Methodologies:Quick creation of limited-capability version or model of systemFocus on refining preliminary system or model, not fully describing it on paper
21Compare and contrast extreme programming and throwaway prototyping.
22Extreme programming (XP): Extreme Programming is founded on four core values which provide a foundation on which XP developers use to create any system. The four core values are Communication, Simplicity, Feedback and Courage.Throwaway Prototyping: Throwaway prototyping-based methodologies balance the benefits of well thought out analysis and design phases with the advantages of using prototypes to refine key issues before a system is built. Each of these issues is examined by analyzing, designing, and building a design prototype.
23Describe the major elements and issues with waterfall development.
24Waterfall Development follows life cycle Requires that system requirements be precisely specified prior to implementationEffort devoted to specifying requirements is a strengthIssue: Specifying requirements on paper is laborious and may lead to errors and omissionsIssue: Freezing requirements during development helps assure that system is developed according to specifications, but in a dynamic business environment, system that is ultimately developed may bear little resemblance to what is actually needed
25Describe the major elements and issues with parallel development.
26The parallel development methodology attempts to address the problem of long delays between the analysis phase and the delivery of the system. Instead of doing design and implementation in sequence, it performs a general design for the whole system and then divides the project into a series of distinct subprojects that can be designed and implemented in parallel. Once all subprojects are complete, there is a final integration of the separate pieces, and the system is deliveredThe major issues in this approach are that it still suffers from problems caused by paper documents. It also adds a new problem such as sometimes the subprojects are not completely independent; design decisions made in one subproject may affect another, and the end of the project may require significant integration efforts.
27Describe the major elements and issues with phased development.
28Phased Development: RAD methodology Does not attempt to develop complete systemSystem is generally specifiedRequirements are organized into versionsFirst version includes essential system components and is delivered to users quickly.Subsequent versions add features and refinementsIssue: Accurately specifying initial requirements so that first version provided to users is useful, although incomplete.
29Describe the major elements and issues with prototyping.
30Prototyping collapses analysis, design, and implementation into one phase This phase is cycled through several times until system meets user needsA "rough" version of system is developed early and rapidly, and user feedback is solicited.Based on user comments, system is modified and refined repeatedlyUltimately, system will be refined to point where users accept it and it can be put into productionPrototyping provides rapid delivery of a system, but haste to get "something" to users quickly may lead to poor specification of prototype
31Describe the major elements and issues with throw-away prototyping.
32Throw-away prototyping merges prototyping and SDLC Prototypes of various system elements are developed to explore design alternatives and refine system requirementsPrototype helps users clarify requirements, then it is discarded, but its requirements are incorporated into systemUseful in situations where users are uncertain about key elements of the system
33What are the key factors in selecting a methodology?
34There are several factors that influence the choice of a methodology: Clarity of the user requirementsFamiliarity with the base technologySystem complexityNeed for system reliabilityTime pressures &Need to see progress on the time schedule.
36Business analyst: Emphasis on the business issues addressed by the system: value of new system; identification of problems and opportunities; revision of business processes and policies.Systems analyst: Emphasis on IS issues of the system: how IT can be used to support business processes; design of new business process and IS; and enforcement of IS standards.Infrastructure analyst: Technical issues associated with integrating new system components to existing technical infrastructure. Change management analyst - emphasis on facilitating organizational adaptation to new system. Helping to identify and overcome resistance to change and assuring adequate training and documentation of new system.Project manager: Ensuring that progress is made on the project: time schedules and budgets are met; supervision of project team; and manage relations with project sponsor and users.
37Compare and contrast the role of a systems analyst, business analyst, and infrastructure analyst.
38System Analyst: A System Analysts role is to: Identifying how technology can improve business processesDesigning the new business processesDesigning the information systemEnsuring that the system conforms to information systems standardsBusiness Analyst: A Business Analyst’s role is to:Analyzing the key business aspects of the systemIdentifying how the system will provide business valueDesigning the new business processes and policiesInfrastructure Analyst: The Infrastructure Analyst’s role is to:Ensuring the system conforms to infrastructure standardsIdentifying infrastructure changes needed to support the system
39Which phase in the SDLC is most important and why?
40All systems development projects follow essentially the same fundamental process called the system development life cycle (SDLC).The planning phase in SDLC is the most important phase because during this phase the project team identifies the business value of the system, conducts a feasibility analysis, and plans the project.Planning phase is the fundamental process of understanding why an information system should be built and determining how the project team will go about building it.