Essentials of Systems Analysis and DesignOverview of LectureSome Key DefinitionsSystems Development MethodologySystems Analysis and Design: Core ConceptsSlide 6Systems Development Life CycleSlide 8Slide 9Slide 10Phases of the Systems Development Life CycleProject Identification and SelectionProject Initiation and PlanningProject PlanningSlide 15Slide 16Slide 17MaintenancePowerPoint PresentationWhen to Use SDLCAdvantages of SDLCDisadvantages of SDLCThe Cost of Change The Systems Development Life CycleApproaches to DevelopmentPrototypingSlide 26When to use PrototypingAdvantages of PrototypingDisadvantages of PrototypingSlide 30Joint Application Design (JAD)Joint Application Design1-1Essentials of Systems Analysis and DesignChapter 1:Foundations for Systems Development1-2Overview of LectureInformation Systems ConceptsTypes of Information SystemsApproaches to Systems DevelopmentSystems Development Life CyclePrototypingJoint Application Design1-3Some Key DefinitionsData: raw facts; collected, not organized.Information: data organized in a meaningful way.Knowledge: information organized to convey understanding, experiences, accumulated learning, or expertise.1-4Systems Development MethodologyA standard process followed in an organization to conduct all the steps necessary to analyze, design, implement and maintain information systems1-5Systems Analysis and Design: Core ConceptsMajor goal: to improve organizational systems by developing or acquiring software and training employees in its useApplication software, or a system, supports organizational functions or processes1.81.81-6Systems Analysis and Design: Core ConceptsSystem: Turns data into information and includes:Hardware and system softwareDocumentation and training materialsJob roles associated with the systemControls to prevent theft or fraudThe people who use the software to perform their jobs1-7Systems Development Life CycleSystem Development MethodologyStandard process followed in an organizationConsists of:•Investigation/Planning•Analysis•Design•Implementation•Maintenance1.71.71-8Systems Development Life CycleThe traditional methodology used to develop, maintain, and replace information systems1-9Systems Development Life CycleSeries of steps used to manage the phases of development for an information systemConsists of four phases:Planning and SelectionAnalysisDesignImplementation and OperationMost texts include a fifth phase Maintenance of the Information System1.91.91-10Systems Development Life CyclePhases are not necessarily sequential•Generally, the steps are performed sequentially•Backwards looping between steps occurs but can be costlyEach phase has a specific outcome and deliverableIndividual companies use customized life cycle1.101.101-11Phases of the Systems Development Life CycleSystems Planning and SelectionTwo Main Activities•Identification of Need/Project Selection•Investigation and Determination of Scope•Preliminary Planning and Scheduling1.111.111-12Project Identification and SelectionAn organization’s total information systems needs are identified, analyzed, prioritized, and arranged1-13Project Initiation and PlanningA potential information systems project is explained and an argument for continuing or not continuing with the project is presented; a detailed plan is developed for conduction the remaining phases of the SDLC for the proposed system1-14Project PlanningIS Project SelectionScreening Committee vs. Managerial DecisionFocus on strategic goals and objectivesMandatory vs Optional projectsIS development projects planning and managementPERT (Program Evaluation and Review Technique)GANTTPreliminary Budget Preparation1-15Phases of the Systems Development Life CycleSystems AnalysisStudy of current procedures and information systems•Determine requirements•Generate alternative designs•Compare alternatives•Recommend best alternative1.151.151-16Systems Development Life CycleSystem DesignLogical Design•Concentrates on business aspects of the systemPhysical Design•Technical specificationsImplementation and OperationImplementation•Hardware and software installation•Programming•Testing•User Training•Documentation1.161.161-17Systems Development Life CycleOperation and Maintenance•System changed to reflect changing conditions•System obsolescence1.171.171-18MaintenanceThe final phase of the SDLC in which an information system is systematically repaired and improved1-191.191.191-20When to Use SDLCHighly Structured ApplicationsWell Defined RequirementsLarge Transaction Processing SystemsUser Experience in IS is high1-21Advantages of SDLCUser sign off at each stage documents users requirementsDefinitive systems requirements“There is an End”Proven MethodUsed with complex problems1-22Disadvantages of SDLCVery resource intensiveInflexible; Inhibits changesLimited User InvolvementNo visible model of system until final stagesLast minute changes are very costly1-23The Cost of ChangeThe Systems Development Life CycleAnalysis $10Design $100Development $1000Implementation $10,000Maintenance $100,0001-24Approaches to DevelopmentPrototypingAn iterative process of systems development in which requirements are converted to a working system that is continually revised through close work between the analyst and the usersBuilding a scaled-down working version of the system and refining it until the user is satisfiedAdvantages:•Users are involved in design•Captures requirements in concrete form1.241.241-25PrototypingIdentify basicrequirementsDevelop aworking prototypeUse the prototypeIs usersatisfiedRevise and Enhance the PrototypeOperationalprototypeYes No1-261.261.261-27When to use PrototypingIll-defined requirementsUnpredictable user behaviorLow experience of user in ISImmediate results are desiredHigh number of alternate solutions1-28Advantages of PrototypingUser involvement in analysis and design Ability to capture requirements in concrete, rather in the abstractUser satisfactionFast development timeFewer errors and design flawsMore opportunity for changesAllows for fine-tuning1-29Disadvantages of PrototypingRequires time and cooperation between users and IS personnelTotal development costs can be higherProject does not have an