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1 Systemutveckling Chapter eleven overview SECTION 11.1 – DEVELOPING ENTERPRISE APPLICATIONSDeveloping SoftwareThe Systems Development Life CycleSoftware Development MethodologiesDeveloping Successful SoftwareSECTION 11.2 – THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)Systems Development Life CyclePhase 1: PlanningPhase 2: AnalysisPhase 3: DesignPhase 4: DevelopmentPhase 5: TestingPhase 6: ImplementationPhase 7: MaintenanceSoftware Problems are Business Problems
2 11.1. DEVLOPING ENTERPRISE APPLICATIONS Software that is built correctly can transform as the organization and its business transformsSoftware that effectively meets employee needs will help an organization become more productive and enhance decision makingSoftware that does not meet employee needs may have a damaging effect on productivity and can even cause a business to failDiscuss the famous Nike SCM failureOrganizations must learn how to build and implement disruptive technologies, such as software for wireless devices, to remain competitiveSoftware that is built correctly can support agile organizations and can transform as the organization and its business transformsSoftware that effectively meets employee needs will help an organization become more productive and enhance decision makingSoftware that does not meet employee needs may have a damaging effect on productivity and can even cause a business to fail
3 Vad är en IS-utvecklare? Ingenjör, konstruktör, tekniker?ellerDesigner, kreatör, konstnärCitatProgrammining is funDeveloping quality software on a business basis is hard
4 Kvalitet i system PRODUCT REVISION - Maintainability Can I fix it ? - Flexibility Can I change it ?- Testability Can I test it ?PRODUCT TRANSITION- Portability Will I be able to use it on another machine ?- Reusability Will I be able to reuse some of the software ?- Interoperability Will I be able to interface it with another system ?PRODUCT OPERATIONS- Correctness Does it do what I want ? Vanligast- Reliability Does it do it accurately all of the time ?- Efficiency Will it run on my hardware as well as it can ?- Integrity Is it secure ?- Usability Is it well designed for the user ?+ Does it do the right thing ?+ Is it economically relevant ?
5 Systemdiagnos ur användarens perspektiv Verksamhetsstöd. Frågor som rör informationens aktualitet, riktighet och fullständighet och om systemfunktionerna passar verksamheten. Ex ”Är info från systemet så fullständig att den kan användas direkt ?”Funktionalitet. Frågor om hur lätt det är att använda systemet, svarstider etc. Ex ”Erhålls info vid rätt tidpunkt ?”Kunskap och support. Frågor som rör dokumentation och utbildning. Ex ”Tycker Du att systemets bruksanvisning är lätt att förstå?”. Går det att få hjälp ?Systemförvaltningsorganisation. Frågor som rör ansvar och befogenheter i samband med systemets drift. Ex ”Sker uppföljning av onormala händelser i systemet ?”. ”Korrigeras fel inom rimlig tid?”Tillgänglighet. Är systemet alltid tillgängligt då jag har behov av det?Säkerhet och skydd Är data tillräckligt säkrade och skyddade?
6 Utvecklingsprinciper enligt RUP KravdrivenArkitektur-fokuseradRisk-fokuseradKomponentinriktadIterativKvalitet i fokusHantera ändringar
7 CMM - Kvalitet i utvecklingsprocessen Level 1- INITIALProcesses are ad hoc and sometimes chaotic. Because few processes are defined, successful projects often depend on heroic individual effort.Level 2- REPEATABLEBasic project management processes are used to track cost, schedule, and functionality. The discipline exists to repeat previous success with similar projects.Level 3- DEFINEDBoth management and technical processes are documented and integrated into a standard software process for the organization. Projects use an approved, tailored version of the standard software processes.Level 4- MANAGEDDetailed measures of the software process and product quality are collected and that information is used to understand both the product and the process in quantitative terms.Level 5- OPTIMIZINGContinuous process improvement is facilitated by quantitative feedback from the process and by doing pilot studies of innovative ideas and technologies.
8 The systems development life cycle (sdlc) CLASSROOM EXERCISEAround SDLCBreak your students into groups and have them correlate the SDLC to building a house.This activity helps students understand the different types of activities that occur during each phase of the systems development life cycleHave your students present their answers to the entire class
9 The systems development life cycle (sdlc) Planning phase – project goals - förstudieAnalysis phase – Business requirements – Krav/RequirementsDesign phase – involves describing the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentationDevelopment phase – involves taking all of the detailed design documents from the design phase and transforming them into the actual systemTesting phaseImplementation phase – involves placing the system into production so users can begin to perform actual business operations with the systemMaintenance phase – involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goalsCLASSROOM EXERCISESpace Needle ExerciseBreak your students into groups and give them equal materials from a Tinker Toy set, a Zome set, or a product of your choice. Give them each the following instructions and observe the groups as they build their prototypes.Review the IM for details on the project
11 Software development methodologies There are a number of different software development methodologies including:WaterfallRapid application development (RAD)Extreme programmingAgileWaterfall methodology – a sequential, activity-based process in which each phase in the SDLC is performed sequentially from planning through implementation and maintenanceRapid application development methodology (RAD) – emphasizes extensive user involvement in the rapid and evolutionary construction of working prototypes of a system to accelerate the systems development processExtreme programming (XP) methodology – breaks a project into tiny phases, and developers cannot continue on to the next phase until the first phase is completeAgile methodology – a form of XP, aims for customer satisfaction through early and continuous delivery of useful software components
12 Utvecklingsprinciper, en annan indelning TOTAL/-HELHETS-ANSATS (Bokens Waterfall method)Helheten specificeras, konstrueras och implementerasITERATIV PRINCIPTillverka i olika utgåvor:1.0, 1.1, …………Skillnaden mellan två utgåvor kan vara att man fördjupat komplexiteten, ex bilder med animation. Skälet till att arbeta iterativt kan vara att utvecklingsteamet är inte moget för en totalansats eller att man vill pröva och lära ny sig teknikINKREMENTELL PRINCIPEtt inkrement är att man lagt till en funktion, ex en statistikfunktion. Skälet är att man vill införa en produkt etappvis av ekonomiska eller av andra skäl
13 Rapid Application Development Methodology (RAD) Rapid application development methodology (RAD) – emphasizes extensive user involvement in the rapid and evolutionary construction of working prototypes of a system to accelerate the systems development processThe prototype is an essential part of the analysis phase when using a RAD methodologyPrototype – a smaller-scale representation or working model of the users’ requirements or a proposed design for an information systemRAD is a more popular route for system development projectsThe fundamentals of RAD include:Focus initially on creating a prototype that looks and acts like the desired systemActively involve system users in the analysis, design, and development phasesAccelerate collecting the business requirements through an interactive and iterative construction approach
14 XP – Extreme Programming. Lättrörlig utveckling(Agile) Project boardKrav Test fall Komponenter som skall skapasTIMEBOXEDDAGLIGTest-processTeamAnvändare ProgrammerareParBygg-processGer kontinuerligt användbara resultat: Tillfredställelse och trovärdighet
15 Också systemutveckling: Standardsystem – Köpta system
16 Processen för att köpa system BehovsanalysFörutsättningsanalysMarknadsundersökningLeverantörsbedömningOffertbegäranJämförelseUrvalDemonstrationBehovskompletteringUtvärderingPrimärvalTestkörningFörhandlingBeslutDelgivningKälla ’Att välja Standardsystem.’ Anveskog m.fl.
17 Att köpa system – fördelar & nackdelar Möjliga FördelarUtprövat - fungerarSnabbare installationBilligare utveckling och underhållSäkrare kalkylErfarenhet inbyggd i systemetSamordnad verksamhetLeverantören utvecklar och anpassar till nya plattformar etc.Möjliga NackdelarFörhastade beslutUnderskattning av anpassningsbehovÖveranpassningTäcker endast en del av kravområdetLeverantörsberoende
18 Också systemutveckling: End user development ExempelAccess + SQLDefiniera formulär och databastabellerFront PageKonstruktion av webbsidorExcelSkapa ”ekonomisystem”Fler ?
19 Verifiera och validera ProblemÖnskemålBeställningKravspecSystemValidera(Genomgångar& användning)Verifiera(Tester)
20 11.2. THE SYSTEMS DEVELOPMENT LIFE CYCLE SDLC Large, complex IT systems take teams of architects, analysts, developers, testers, and users many years to createThe systems development life cycle is the foundation for many systems development methodologies such as RAD and agileSystems development life cycle – the overall process for developing information systems from planning and analysis through implementation and maintenanceCLASSROOM OPENERFinding a Good FitProjects fail for a number of varied reasons. Nick Baker, a 37-year-old system architect at Microsoft, knows that well. A British transplant at the software giant's Silicon Valley campus, he went from failed project to failed project in his career. He worked on such dogs as Apple Computer's defunct video card business, 3DO's failed game consoles, a chip startup that screwed up a deal with Nintendo, the never successful WebTV and Microsoft's canceled Ultimate TV satellite TV recorder.But Baker finally has a hot seller with the Xbox 360, Microsoft's video game console launched worldwide last holiday season. The adventure on which he embarked four years ago would ultimately prove that failure is often the best teacher. His new gig would once again provide copious evidence that flexibility and understanding of detailed customer needs will beat a rigid business model every time. And so far the score is Xbox 360 one and the delayed PlayStation 3 nothing.
21 SDLC Walk the students through the systems development life cycle: Planning phase – involves establishing a high-level plan of the intended project and determining project goalsAnalysis phase – involves analyzing end-user business requirements and refining project goals into defined functions and operations of the intended systemDesign phase – involves describing the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentationDevelopment phase – involves taking all of the detailed design documents from the design phase and transforming them into the actual systemTesting phase – involves bringing all the project pieces together into a special testing environment to test for errors, bugs, and interoperability, in order to verify that the system meets all the business requirements defined in the analysis phaseImplementation phase – involves placing the system into production so users can begin to perform actual business operations with the systemMaintenance phase – involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goals
22 Primary planning activities include PHASE 1: PLANNINGPlanning phase – involves establishing a high-level plan of the intended project and determining project goalsPrimary planning activities includeIdentify and select the system for development (Se nästa bild)Assess project feasibilityDevelop the project planAsk your students if any of them have ever been involved in the planning phase for a systems development effortAsk them to list additional activities they might have performed during the planning phaseAsk your students to keep in mind that there are literally hundreds of different additional activities that could be performed during each phase
23 Förändringsanalys Nulägesanalys Kartlägg verksamheten, dess ärendeflöden och dess processer.Kartlägg funktioner i nuvarande system.FörändringsanalysLista problem, orsaker och konsekvenserGör en målmodell och definiera CRF (Critical Success Factors)Analysera möjligheter/ åtgärder och effekter. Helst ekonomiskt kvantifieradePrioritera möjligheter/ åtgärderVälj strategi/ åtgärder och avgränsa systemområdetBeskriv önskat lägeFunktioner i nytt system. Översiktligt/ grovt beskrivna.Nya ärendeflöden och verksamhetsprocesser.
24 Identify and Select the System for Development Discuss each of the evaluation criteria discussed in the FigureValue chain analysis – systems with greater value are given priority over systems with less valueStrategic alignment – projects that are in line with the organization's strategic goals and objectives are given priority over projects not in line with the organization's strategic goals and objectivesCost/benefit analysis – determines which projects offer the organization the greatest benefits with the least amount of costResource availability – determine the amount and type of resources required to complete the project and determine if the organization has these resources availableProject size, duration, and difficulty – determine the number of individuals, amount of time, and technical difficulty of the project
25 Assess Project Feasibility Feasibility study – determines if the proposed solution is feasible and achievable from a financial, technical, and organizational standpointDifferent types of feasibility studiesEconomic feasibility studyOperational feasibility studyTechnical feasibility studySchedule feasibility studyLegal and contractual feasibility studyRiskanalysStora system innebär riskOkänt område innebär riskEconomic feasibility study – (cost-benefit analysis) – identifies the financial benefits and costs associated with the systems development projectOperational feasibility study – examines the likelihood that the project will attain its desired objectivesTechnical feasibility study – determines the organization’s ability to build and integrate the proposed systemSchedule feasibility study – assesses the likelihood that all potential time frames and completion dates will be metLegal and contractual feasibility study – examines all potential legal and contractual ramifications of the proposed systemWhich type of feasibility study would be appropriate for each of the following:Implementation of a new payroll systemImplementation of a new CRM systemImplementation of a new module to an existing CRM systemImplementation of a new ERP systemImplementation of a additional functionality to an existing KM system
26 Develop the Project Plan Developing the project plan is a difficult and important activityThe project plan is the guiding force behind on-time delivery of a complete and successful systemContinuous updating of the project plan must be performed during every subsequent phase during the SDLC
27 Primary analysis activities include: Gather business requirements PHASE 2: ANALYSISAnalysis phase – involves analyzing end-user business requirements and refining project goals into defined functions and operations of the intended systemPrimary analysis activities include:Gather business requirementsCreate process diagramsPerform a buy vs. build analysisAsk your students which analysis activity is the hardestAns: Gathering business requirements is the typically one of the hardest tasks to perform on any project and is the number one reason why projects fail “Bad Business Requirements”Why is gathering business requirements so difficulty?It takes many different people to perform organizational activities and they all have to be involved in writing the business requirementsWriting detailed business requirements is difficult (review closing case two – Reducing Ambiguity in Business Requirements)Business requirements continuously change
28 Gather Business Requirements Business requirements – the detailed set of business requests that the system must meet in order to be successfulDifferent ways to gather business requirementsJoint application development (JAD) session – where employees meet to define or review the business requirements for the systemInterviewsQuestionnairesObservationsReview business documentsWhat other methods could you use to gather business requirements?Comparing different organizations’ processes with best of breed processes – for example looking at Dell’s supply chainComparing across industries, for example reviewing CRM practices in different hotels and restaurants to apply to a utensil manufacturerReviewing magazines, articles, and literature to determine new processes, technology, and innovation
29 Gather Business Requirements The system users review the requirements definition document and determine if they will sign-off on the business requirementsRequirements definition document – contains the final set of business requirements, prioritized in order of business importanceSign-off – the system users’ actual signatures indicating they approve all of the business requirementsWhy is obtaining a physical “sign-off” such a big deal?When someone is asked to put their actual signature on something they take it much more seriously than just a verbal OK. For this reason, asking someone to sign-off helps to ensure they are actually reading the document, understanding the document, and most importantly, in agreement with the document.Ask your students how they would treat a situation where they were asked to sign a document that details their exact net worth. Chances are they would be sure to review it inside out and upside down, as the ramifications of an inaccurate net worth can cause a myriad of issues such as bad credit and the inability to obtain a mortgage.
30 Avvägning och balans krävs Datorns styrkaAlltid tillgängligKan överblicka stora datamängderArbetar snabbtUtföra arbete på ett systematiskt och likartat sättKommer ihågMänniskans styrkaFantasiGöra bedömningarUpptäcka onormala händelserFörståelseFörmåga att bedöma och se helhetenHantera avvikelserMänskliga behovAnvända kunskaperMeningsfullhetSjälvständighetSociala kontakterBalans jobb-fritidBALANSFöretagets kravLönsamhetFlexibilitetUtvecklingSamarbete med andraKundrelationerproduktutveckling
31 Två typer av design Användarcentrerad Utgå från arbetssituationen Datorisera för att stödja och underlättaTeknikcentreradUtgå från arbetsuppgiften och datorns möjligheterAnvändaren följer systemet och kompletterar datornExempelAC : Programmen klarar fler steg i arbetsflödet sammanhängandeTC: Användaren får skifta program mellan olika moment i arbetetAC: Användaren kan registrera en del av ett ärende och sedan göra tillfälligt uppehållTC: Databasens kontroller kräver att alla registreringar måste vara kompletta
32 Olika grader av Datorstyrning Datorstött arbete. Människan avgör. Ex. En ekonom använder ExcelDatorlett arbete. Systemet ger vägledning. Ex. En resebyråtjänsteman bokar en resa via ett systemDatorstyrt arbete. Systemet styr och beordrar. Ex. I ett automatiskt lager hämtas varor fram automatiskt och en lampa lyser på det som skall plockasDatoriserat arbete. Systemet har tagit över. Ex. RobotiseringTre grundläggande situationerHelt manuellt arbeteSamarbete mellan människa och dator. VANLIGAST OCH SVÅRASTHelt automatiserat arbete
33 Användarvänlighet Exempel på intressanta egenskaper för ett system Enkelt att lära, intuitivtLättförståeligt och logiskt uppbyggtFöljer samma standard som övriga system i företagetTilltalande layoutKunna navigera via menyer och kunna använda genvägarTollerant för felstavningar etcFå avbrottSnabbtMöjligheter att korrigera misstagMöjlighet att få förklaringar och hjälpMöjlighet att göra uppehåll i arbetet
34 Olika grader av användarengagemang i utvecklingsprocessen Bild ur: Alter, Information Systems
35 Create Process Diagrams Process modeling – graphically representing the processes that capture, manipulate, store, and distribute information between a system and its environmentCommon process modeling diagrams includeData flow diagram (DFD) – illustrates the movement of information between external entities and the processes and data stores within the systemComputer-aided software engineering (CASE) tools –automate systems analysis, design, and developmentCLASSROOM EXERCISEUnderstanding Business RequirementsOne of the primary reasons why projects fail is due to missing or inaccurate business requirements. This is a great exercise to demonstrate to your students why it is so difficult to gather complete and accurate business requirements. Break your students into groups and provide your students with the instructions below, a piece of blank paper, and two different colored markers.Please create the following picture using the materials provided. Frame 3 inches by 5 inches Use two different colors Use one color for the 3 inches and the other color for the 5 inches Object 1 – Sun Using one color create a solid circle in the top right corner of your frame Create five small lines using the same color coming out from the sun Create five even smaller lines using a different color and place them coming out of the sun Object 2 – Ground The ground should be one color and one inch along the bottom of the picture Place one long line of along the top of the ground Place five circles ½ inch apart along the bottom of the grass Object 3 – Snowman Using one color create three different shaped circles The first circle should be the size of a quarter The second circle should be the size of a nickel The third circle should be the size of a dime Place the first circle in the middle of the picture on top of the ground Place the second circle in the middle of the picture on top of the first circle Place the third circle in the middle of the picture on top of the second circle Using a different color create two small eyes and place them in the middle of the third circle Using the same color as mentioned above, create three small buttons and place two on the second circle and one on the first circle Use four 2 inch pieces to create the snowman’s arms Object 4 – Broom Place 10 small pieces on top of a small circle Create the broom handle by attaching two long pieces to the top of the broom Place the broom in the snowman’s handOnce everyone has completed their pictures, have them take a walk around the class to see what the other groups created. You can be guaranteed that no two pictures will look alike although they were all working off the exact same requirements. This was a simple picture and there was so much ambiguity in the requirements that all of the pictures are different. If this were representative of a real system, then the requirements would have to be so perfect and detailed that all of the pictures would have turned out identical. The biggest issues with business requirements are ambiguity and interpretation.
36 Create Data Flow Diagrams AnvändareFunktion i systemetDataflöde/transaktionDatalagring/DataBasDiscuss the sample data flow diagram with your studentsExplain that the entities send data or requests to processesThe processes interact with the data storesExplain to your students that process diagrams are typically performed by a combination of both IT and business personnelIT personnel understand the technology, and business personnel understand the business process, and they are both required to work together to accurately model a systemBild ur: Alter, Information Systems
37 DFD kan förstoras Context-nivå Ur INFORMATION SYSTEMS, PrenHall - Alter
38 DFD - FörstoringUr INFORMATION SYSTEMS, PrenHall - Alter
39 Funktioner i systemet - Användningsfall (Use-case) 5 val av läsk + ångerknapp. Automaten returnerar växel.Use CaseActorSystemetSystem eventsStoppa i pengarÅngraVal av läskSystem operationsMata ut läskReturnera pengarKöpa läskKundFylla på läskTömma pengarLeverantörButiksägareAv/påServiceKontraktEn Actor kan förutom människa vara ett annat system eller en maskin
40 Funktioner i systemet - Användningsfall (Use-case), forts. System eventsReg kundReg varorTryck klarActorSystemetBeställa varaOrder behandlareFaktureraReg lagerplockLager personalUppdateradatabasSystem admKopiera databas
41 Beskrivning av IS-funktioner – Use-Case/ Anv.fall Namn: SaleDescription: Perform a customer sale eventActor: CashierStakeholders & Interests: Kund, personal, ekonomiavdelningen …..Success scenario: Start sale enter items, end sale, recieve paymentAlernate scenarios: Pay cache/card, item is missing,………Two cuolumn eventsActor System1. enter Item-nr display item name, quantity in stock2. enter quantity confirm ………..……..Precondition: Cashier logged inPostcondition: Sale registred, receipt printedEvents: Start sale enter items, end sale, recieve paymentLogic: If the customer……… If the article…….. If the credit card ……...User InterfaceData som användsSale
42 Funktioner i systemet - Annan graf Client - functionsF2Huvud menyF4F3Server - functions
43 Samband IS-funktioner & Verksamhets-processer Systembeskrivning VerksamhetsbeskrivningF1Order processF1 Order regF2Lager processKundF2 Lager transF3 FaktureringFakt processF3Leverans process
44 Icke-funktionella krav PRODUCT REVISION- Maintainability Can I fix it ?- Flexibility Can I change it ?- Testability Can I test it ?PRODUCT TRANSITION- Portability Will I be able to use it on another machine ?- Reusability Will I be able to reuse some of the software ?- Interoperability Will I be able to interface it with another system ?PRODUCT OPERATIONS- Correctness Does it do what I want ?- Reliability Does it do it accurately all of the time ?- Efficiency Will it run on my hardware as well as it can ?- Integrity Is it secure ?- Usability Is it well designed for the user ?+ Does it do the right thing ?+ Is it economically relevant ?
45 Perform a Buy vs. Build Analysis An organization faces two primary choices when deciding to develop an information systemBuy the information system from a vendorCommercial off-the shelf (COTS) – software package or solution that is purchased to support one or more business functions and information systemsSCM, CRM, and ERP solutions are typically COTSBuild the information system itselfPerforming a buy vs. build analysis is a difficult taskCLASSROOM EXERCISECOTS AnalysisBreak your students into groups and assign each group one of the following:Buy a COTS CRM system from SiebelBuild a COTS CRM system similar to SiebelHave each team find support for the decision they have been given using the Internet, textbooks, magazines, etc.Once the students have finished building a case that can support their decision, break the room into two sections – one side representing the “buy decision” and one side representing the “build decision”Let the students debate each other and determine if the ultimate decision is a buy or a build
46 Primary design activities include: Design the IT infrastructure PHASE 3: DESIGNDesign phase – involves describing the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentationPrimary design activities include:Design the IT infrastructureDesign Functions in detailFor review, the IT infrastructure includes the hardware, software, and telecommunications equipment that, when combined, provide the underlying foundation to support the organization's goalsOrganizations need a solid IT infrastructure to support their IT systemsIT infrastructure must meet the organization’s needs in terms of time, cost, technical feasibility, and flexibility
47 Design the IT Infrastructure Sample IT infrastructureDiscuss the sample IT infrastructure with your studentsPoint out the Internet cloudThe firewallThe routers, servers, workstations, and printers
48 Design System ModelsModeling – the activity of drawing a graphical representation of a designDifferent modeling types include:Graphical user interface (GUI)System Functions (DFD and Program logics)Data modelTransactionsGraphical user interface (GUI) – the interface to an information systemGUI screen design – the ability to model the information system screens using icons, buttons, menus, and submenusData models – a formal way to express data relationships to a database management system (DBMS)Entity relationship diagram (ERD) – a technique for documenting the relationships between entities in a databaseIf you had to equate building a system to building a house what would occur during the design phase that is similar to modeling?Designing the house in a blueprint
49 Design Data Models Sample entity relationship diagram (ERD) Discuss the sample ERD with your studentsPoint out the entities and attributesDiscuss the relationships
50 Design - Arkitektur Logiskt Dela in SW i delsystem Dela in SW i lager Fördela SW på HW, ex client-serverSyfteFlexibla system med utbytbara delarKunna fördela arbetet på olika grupperKunna testa systemet systematiskt
51 Design - Teknik SW Operativsystem Kommunikationssystem DatabashanteringssystemUtvecklingsmiljö/ programmeringsspråk. Ex .NET och JAVAHWDatorerKommunikationsutrustningetc.Principer, standards och produkter
52 Design - Realtid Händelser Kontroll/ styrning Analys av systemets olika tillstånd och statusSynkroniseringParallella processerPrioriteringsmekanismerSäkerställande av att dead-lines hållsetc.Principer, standards och produkter
53 Design - User interface Web-gränssnittMultimediaHjälpfunktioneretc.Principer, standards och produkter
54 Beskrivning av logik i IS-funktioner - Text ORDERREGISTRERINGTryck NYORDER. Kundnummer slås in, systemet visar kunddata. Saknas kunden skall kunddata kunna registrerasEtt antal artikelnummer och kvantiteter registrerasSystemet visar artikeldataSystemet verifierar att önskad kvantitet finnsEfter KLAR summeras ordern och visas i sin helhet på skärmenOK resulterar i att ordern skickas till leveransfunktionen. Vidare subtraheras relevanta lagerkvantiteter
55 Beskrivning av IS-funktioner – Mer strukturerad text INPUT Kund- och resedataBEARBETNING Boka biljett i databasen ………..OUTPUT Skriv ut biljett på skrivaraUSER INTERFACE Frame - 7VOLYMER transaktioner per dag15 Mb data i databasenPRESTANDAKRAV Max väntetid: 3 sekunderTILLGÄNGLIGHET 24 timmar per dygn
56 IS-funktioner - logik - struktured language BEGINIF lagersaldo < miniminivåTHEN skapa inköpsorderELSE do nothingEND
63 Primary development activities include: Develop the IT infrastructure PHASE 4: DEVELOPMENTDevelopment phase – involves taking all of the detailed design documents from the design phase and transforming them into the actual systemPrimary development activities include:Develop the IT infrastructureDevelop the database and programs+ Dokumentation m.mDevelopment 1: Develop the IT InfrastructureThe platform upon which the system will operate must be built prior to building the actual systemIn the development phase, the organization purchases and implements the required equipment to support the IT infrastructureDevelopment 2: Develop the database and programsOnce the IT infrastructure is built, the organization can begin to create the database and write the programs required for the systemIT specialists perform the majority of the tasks associated with the development phase
64 Primary testing activities include: Write the test conditions PHASE 5: TESTINGTesting phase – involves bringing all the project pieces together into a special testing environment to test for errors, bugs, and interoperability, in order to verify that the system meets all the business requirements defined in the analysis phasePrimary testing activities include:Write the test conditionsPerform the system testingWhy is testing so important during the SDLC?Without testing you could release a bad product into the market, which would severely hinder your reputation
65 Write the Test Conditions Test condition – the detailed steps the system must perform along with the expected results of each stepExplain to your students that a typical system can have tens of thousand of test conditions.Ask your students how many test conditions would be required to test Microsoft Word Cut and Paste functionality onlyAsk your students how many test conditions to test all the different combinations of font, font size, font style, and different lengthsHere a few sample test conditions for an example:Cut Times New Roman, Font size 10, Bold, Italic, Two wordsCut Times New Roman, Font size 11, Bold, Italic, Two wordsCut Times New Roman, Font size 10, Bold, underline, Two wordsCut Times New Roman, Font size 11, Bold, underline, Two wordsCut Times New Roman, Font size 10, Bold, underline, Complete sentenceCut Times New Roman, Font size 11, Bold, underline, Two pages of textPaste Times New Roman, Font size 10, Bold, Italic, Two wordsPaste Times New Roman, Font size 11, Bold, Italic, Two wordsPaste Times New Roman, Font size 10, Bold, underline, Two wordsPaste Times New Roman, Font size 11, Bold, underline, Two wordsPaste Times New Roman, Font size 10, Bold, underline, Complete sentencePaste Times New Roman, Font size 11, Bold, underline, Two pages of textJust imagine all of the thousands of test conditions just with different fonts, per size, per type, per length, and this is just for cut and pasteImagine all of the test conditions to test the advanced mathematical formulas in Excel
66 Perform the System Testing Different types of testingUnit testing – tests each unit of code upon completionApplication (or system) testing – verifies that all units of code work togetherIntegration testing – exposes faults in the integration of software components or unitsBackup and recovery testing – tests the ability of an application to be restarted after failureDocumentation testing – verifies instruction guides are helpful and accurateUser acceptance testing (UAT) – tests if a system satisfies its acceptance criteria+ belastningstesterRank the tests in order of importance for a system releaseAll tests are important and must be performed to ensure a system functions properly and users know how to use it
67 PHASE 6: IMPLEMENTATION Implementation phase – involves placing the system into production so users can begin to perform actual business operations with the systemPrimary implementation activities include:Write detailed user documentationDetermine implementation methodProvide training for the system usersSurprisingly, many projects fail during implementationNo matter how great the system is, if the users do not want the system or cannot use the system, it will fail
68 Write Detailed User Documentation System users require user documentation that highlights how to use the systemUser documentation – highlights how to use the systemAsk your students to discuss situations where they have used user documentation to support an issue or question they were encountering with a systemHow helpful was the documentation?What was wrong with documentation?What could have improved the documentation?Unfortunately, IT system documentation is notoriously difficult to understand and full of errors!! Be sure your users are just as concerned about the documentation that supports the system as they are that the system works.Using the old “Hit by a Bus” metaphor usually helps to ensure the importance of documentation
69 Determine Implementation Method Four primary implementation methodsParallel implementationPlunge implementationPilot implementationPhased implementationParallel implementation – using both the old and the new system until it is evident that the new system performs correctlyPlunge implementation – discarding the old system completely and immediately starting to use the new systemPilot implementation – having only a small group of people use the new system until it is evident that the new system performs correctly and then adding the remaining peoplePhased implementation – implementing the new system in phases, and then implementing the remaining phases of the new systemAsk your student which implementation they would want if they were involved with the implementation of a new CRM systemWhich method contains the least risk?Which method contains the most risk?Which method is easiest for the users?Which method is hardest for the users?
70 Provide Training for the System Users Organizations must provide training for system usersTwo most popular types of training include:Online training – runs over the Internet or off a CD-ROMWorkshop training – set in a classroom-type environment and led by an instructorAsk your students to discuss situations where they have taken online or workshop trainingHow helpful was the training?What was wrong with training?What could have improved the training?
71 Primary maintenance activities include: PHASE 7: MAINTENANCEMaintenance phase – involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goalsPrimary maintenance activities include:Build a help desk to support the system usersPerform system maintenanceProvide an environment to support system changesSystems spend the majority of their life in the maintenance phase
72 Build a Help Desk to Support the System Users Internal system users have a phone number for the help desk they call whenever they have issues or questions about the systemHelp desk – a group of people who respond to internal system user questionsProviding a help desk is an excellent way to provide comprehensive support for new system usersHave you ever used a help desk? Why?Was the help desk useful?Did you get your problem resolved?What could the company have done differently to help you resolve your problem more effectively?
73 Perform System Maintenance Maintenance – fixing or enhancing an information systemDifferent types of maintenance include:Adaptive maintenanceCorrective maintenancePerfective maintenancePreventative maintenanceAdaptive maintenance – increases system functionalityCorrective maintenance – repairs defective systemsPerfective maintenance – enhances systemsPreventative maintenance – reduces chances of system failure
74 Support System Changes An organization must modify its systems to support the business environmentIt typically accomplishes this through change management systems and change control boardsChange management system – a collection of procedures to document a change request and define the steps necessary to consider the change based on the expected impact of the changeChange control board (CCB) – responsible for approving or rejecting all change requestsWhy is change control so important to an organization?Change occurs and an organization must plan for and support system changesWithout changes the organization could not change and grow
75 Software problems are business problems Primary reasons for project failure includeUnclear or missing business requirementsSkipping SDLC phasesFailure to manage project scopeScope creep – occurs when the scope increasesFeature creep – occurs when extra features are addedFailure to manage project planChanging technologyProvide an example of scope creepWe added a new type of discount to our marketing planProvide an example of feature creepWe would like a new logo placed on the top corner of every screen and it should play a song when clicked
76 Software problems are business problems Find errors early: the later in the SDLC an error is found - the more expensive it is to fixExplain to your students that the cost of finding errors grows exponentially the later the error is found in the systems development life cycleAn error found during the analysis and design phase is relatively inexpensive to fixAll that is typically required is a change to a Word documentHowever, exactly the same error found during the testing or implementation phase is going to cost the organization an enormous amount to fix because it has to change the actual systemFind errors early: the later in the SDLC an error is found - the more expensive it is to fix