信息系统管理实践第九章课件information systems management in practice

Technologies for Developing Systems,Chapter 9Information Systems Management In Practice 7EMcNurlin & Sprague,PowerPoints prepared by Michael MatthewVisiting Lecturer, GACC, Macquarie University Sydney Australia,2006 Barbara C. McNurlin. Published by Pearson Education.,9-2,Part III Managing System Development,The next two chapters deal with developing enterprise-based systems through system developmentChapter 9 = we describe the foundations of system developmentTechnologies and methodologiesSystem integration and Inter-organizational System Development Internet-based systemsChapter 10 = we discuss a number of management issuesProject Management the underpinning of successful large projectsIT staffingChange managementLegacy systemsMeasuring the benefits of systems,2006 Barbara C. McNurlin. Published by Pearson Education.,9-3,Part III Managing System Development cont.,System development has traditionally been aimed at procedure-based workProcedure-based activities are large-volume transactions where each transaction has a relatively low cost or valueThese activities, which consist mainly of handling data, are well defined, and the principal measure for gauging their performance is efficiencyInformation systems were, in most cases, first built to automate this kind of work, beginning initially with accounting, and then progressing into manufacturing, administration, sales and marketing, and so onDevelopment of these systems has been handled by IS professionals,2006 Barbara C. McNurlin. Published by Pearson Education.,9-4,2006 Barbara C. McNurlin. Published by Pearson Education.,9-5,Chapter 9,This lecture / chapter reviews this evolution of system development to provide an understanding of the underlying principles of building applicationsIt discusses:Underlying technologiesDevelopment methodologies, andInternet-based systems Case examples include Du Pont Cable Management Services, MGM, Colgate-Palmolive, a telecommunications firm, Hong Kong Exchanges and Clearing and Bekins, with a discussion case on ExxonMobil,2006 Barbara C. McNurlin. Published by Pearson Education.,9-6,Todays Lecture,IntroductionFoundations of Systems DevelopmentStructured DevelopmentFourth-Generation LanguagesSoftware PrototypingComputer-Aided Software Engineering (CASE)Object-Oriented DevelopmentClient-Server Computing System IntegrationERP SystemsMiddleware Inter-organizational System DevelopmentInternet-Based SystemsApplication ServersJavaWeb Services,2006 Barbara C. McNurlin. Published by Pearson Education.,9-7,Introduction,Developing new systems = difficult job -“if anything can go wrong, it will!” though there is progress in improving the process of buildings systems 1970s: system development life cycle1980s: friendly languages and automation of parts of development such as code generation1990s: reliance increased on packages Developer productivity & maintenance,2006 Barbara C. McNurlin. Published by Pearson Education.,9-8,Introduction cont.,Business process reengineering movement = growth on integrated enterprise systems sudden emergence of e-business and Internet based systems2000s - Internet brought need for faster systems development and integrated enterprise systems,Hence new tools for rapid development became available Relying on reusable components & open systems architecture,2006 Barbara C. McNurlin. Published by Pearson Education.,9-9,Introduction cont.,These days, virtually every application is a network application, since the network is becoming the systemWeb-based applications were the first generation of Internet-centric computingThe new field, “Web Services” (or whatever people are calling it), is touted as the secondIn addition, the increasing interconnectedness of supply chains is leading companies to build inter-organizational systems Far more complex undertaking than any single-company systems,2006 Barbara C. McNurlin. Published by Pearson Education.,9-10,Foundations of Systems Development,In the early years, systems development was considered a craftThen = Discipline through structured developmentFigure 9-1 is the classic system development life cycle (waterfall approach)Much touted but rarely (purely) usedDevelopers really always followed the spiral approach as in Figure 9-2,2006 Barbara C. McNurlin. Published by Pearson Education.,9-11,2006 Barbara C. McNurlin. Published by Pearson Education.,9-12,2006 Barbara C. McNurlin. Published by Pearson Education.,9-13,Foundations of Systems Developmentcont.,The Traditional Application Development Approach (characteristics):Hand coding in third generation language, e.g. COBOL“Structured Programming” development methodologyAutomated Project management systemA database management systemA mix of online and batch applications in the same systemDevelopment of mostly mainframe applicationsProgramming by professional programmers onlyVarious automated, but not well integrated s/w toolsA well-defined sign-off process for system deliveryUser participation mainly in require definition and installation phases,2006 Barbara C. McNurlin. Published by Pearson Education.,9-14,Foundations of Systems Development Structured Development,Structured development methodologies accompanied this system development life cycle in an attempt to manage the complexities of systems design and developmentMore discipline: established standards for process and documentation to increase productivity and developers ability to deal with complexityHigher reliability and fewer errors: to catch errors as early as possible through inspectionMore efficient use of resources: thorough project management approaches resulted in:Cost savingsIncreased productivityBetter allocation of human resourcesReduced the tendency for system development project overrunsALL = STILL A PROBLEM!,2006 Barbara C. McNurlin. Published by Pearson Education.,9-15,Foundations of Systems Development Fourth-Generation Languages,Early 1980s 4GLs and Prototyping4GLs are more than just a computer language, they are programming environments. As seen in Figure 9-31980s development fourth generation languages (4GLs). These allowed:End users to develop some programsProgrammers to use different development method = Prototyping,2006 Barbara C. McNurlin. Published by Pearson Education.,9-16,2006 Barbara C. McNurlin. Published by Pearson Education.,9-17,Foundations of Systems Development Software Prototyping,A live, working systemPerforms actual workMay become actual production systemOr replaced by a (newly) coded onePurpose: to test assumptions about:Users requirementsApplication design, or Program logicSoftware system created quickly: language creates codeIterative processEach version performs function in an increasingly efficient mannerBoth 4GLs and prototyping have proven to be important underpinnings for todays application development world,2006 Barbara C. McNurlin. Published by Pearson Education.,9-18,Foundations of Systems Development Computer-Aided Software Engineering (CASE),The advent of Computer Aided Software Engineering (CASE) occurred to automate structured techniques and reduce tediousness of the 1970s structured programming and analysis techniques.Components:Information repository: stores and organizes all information needed to create, modify, and develop software systemFront-end tools: used in all phases that lead up to coding, (“uppercase”)Back-end tools: used to automatically generate source code (“lowercase”)Development workstation: the more powerful the better,2006 Barbara C. McNurlin. Published by Pearson Education.,9-19,Foundations of Systems Development Computer-Aided Software Engineering (CASE) cont.,A late 80s use of CASE (not standard!) is TimeboxingTimeboxing: Technique that uses CASE to guarantee delivery of a system within 120 daysToday, IS departments that aim for speed over complexity are turning to a development technique like:Rapid Application Development (RAD),2006 Barbara C. McNurlin. Published by Pearson Education.,9-20,DUPONT CABLE MANAGEMENT SERVICESCase Example: Rapid Application Development (RAD),To manage its telephones and wiring in its many offices, DuPont needed a cable management systemNo packages on the market could handle its needs, so it called on a DuPont subsidiary to use CASE and timeboxing to build a custom systemDay One was the go-aheadDays 2-30 defined the components of the systemDays 31-90 designed the specs, prototyped the system, and refined the prototype (which became the production system)Days 91-120 installed the system, and a second timebox followedThe resulting system, which took nine months, took others two to three years to develop in-house,2006 Barbara C. McNurlin. Published by Pearson Education.,9-21,Foundations of Systems Development Object-Oriented Development,Object-oriented (OO) development was a revolutionary change in the late 1980s develop objects that can be reusedIt allowed point-and-click programming of graphical user interfacesIt is not so much a coding technique as a code-packaging techniqueObject:Receives request (message)Chooses and executes operation, thenReturns the results to the requesterIt is very modular, so a change in one part of a system need not affect the other parts,2006 Barbara C. McNurlin. Published by Pearson Education.,9-22,Foundations of Systems Development Client-Server Computing and Web Based Development,In the 1990s, two developments became the major news:Client-server systemsWeb-based or network centric developmentUnderlying these two (continuing) trends is the increasing use of packages and system integrationAs much as possible, companies prefer to buy a package rather than build an application in-houseTo develop large applications, they integrate (various) hardware and software components,2006 Barbara C. McNurlin. Published by Pearson Education.,9-23,Foundations of Systems Development Client-Server Computing,These systems split work between a client and a serverFar more flexibility than mainframe-based systemsDesktop: graphics, animation, videoServers: production updatingDidnt always live up to their promise!Clever way to meld the pizzazz of the PC world with the necessary back-end production strengths of the mainframe world,2006 Barbara C. McNurlin. Published by Pearson Education.,9-24,MGMCase Example: Client Server Computing (and Intranet),MGM has a huge library of TV shows and moviesPreviously had over 26 disparate systems on PCsIts first client-server application collected and consolidated all data on the film library so that MGM would know what films they have rights to license to whomMGMs film rights salespeople could visit the head of a cable TV network:Play 2030 second clips of their films using the built-in CD-ROMBrowse the laptops inventory database to verify availability of filmsPrint the licensing deal memo on the spotThe system had a three-tier architecture and was built via prototyping using a RGL development tool,2006 Barbara C. McNurlin. Published by Pearson Education.,9-25,MGMCase Example: Client Server Computing (and Intranet) cont.,Partnering is mandatory with client-server computingRole of IS at MGM changed from systems development and delivery to one of cooperating and partneringRequired a huge cultural shift in the roles and attitudes of the IS staffHardware was cheaper, development was faster and software was cheaper (significant!)Operating costs were more expensive than MGM expectedVersion control of client-server software and service and systems management were more costly,2006 Barbara C. McNurlin. Published by Pearson Education.,9-26,Foundations of Systems Development Summary,These technologies:Structured development4GLsPrototypingCASEOO developmentClient Server systemshave all proven to be foundations of todays system development environmentWe now turn to that (todays) environment, beginning first by discussing the main method of building systems: system integration,2006 Barbara C. McNurlin. Published by Pearson Education.,9-27,Systems Integration,Integration is by far the biggest software problems CIOs face= Why offerings that integrate systems generate so much interestCIOs (and all CXOs!) have long strived to integrate the information systems in their organizationsIntegration =ComplexExpensiveRiskyThree approaches stand out:Database Management Systems: allow applications to share data stored in a single or distributed databaseEnterprise Resource Planning (ERP) Systems: all applications come from a single vendor and are specifically designed to communicate with each otherMiddleware: applications communicate with each other through a third-party translation software - see Figure 9-4Typically = use a combination of all three,2006 Barbara C. McNurlin. Published by Pearson Education.,9-28,Systems IntegrationERP,An ERP system aims to integrate corporate systems by providing a single set of applications from a single vendor operating with a single databaseThe goal provide the means to integrate business departments and functions across an organization History of ERP contains both successes and failures, many of which have been especially notable:Average cost overrun 179% Average schedule overrun 230%Functionally 59% below expectations10% projects completed on time & in budget35% projects cancelledCommon to hold systems large size and complexity responsible as well as:Too much attention to technical aspectsNot enough to organizational aspects,2006 Barbara C. McNurlin. Published by Pearson Education.,9-29,COLGATE PALMOLIVECase Example: Successful ERP,1990s = competitive crisisUsed a decentralized structureExpensive to coordinateSlow to respond to market changesConstraint on company growthVision:“Become a truly global company, with an integrated business environment and standardized business processes.”,2006 Barbara C. McNurlin. Published by Pearson Education.,9-30,COLGATE PALMOLIVECase Example: Successful ERP cont.,After setting up a prototype environment in the US, SAP R/3 module convincingly proved itself as being functional and flexible worldwide for Sales & distributionMaterials management Finance Human resourcesSavings have been made in IT operations complex decentralized IT infrastructure was streamlined,2006 Barbara C. McNurlin. Published by Pearson Education.,9-31,COLGATE PALMOLIVECase Example: Successful ERP cont.,Implementation took five years and cost $430 million, but it was a success. The product delivery cycle dropped and purchasing and other costs were cut Data centers around the world were closed, from 75 down to 2The complexity of its global data networks was also simplifiedSuccess of ERP stems from senior management convincing employees that the company was in crisis and only dramatic change could remedy it,2006 Barbara C. McNurlin. Published by Pearson Education.,9-32,Systems IntegrationMiddleware,Most organizations have a wide range of applicationsNew and oldFrom a variety of vendorsRunning on numerous platformsReplacing or rewriting these systems not an option One option = employ a class of products known as middlewareSoftware that works between and connects applications allowing them to share dataNeeded as wide range of applications used and run on numerous platformsSimplifies development by acting as the “glue” that binds the components togetherThere is a wide variety available as illustrated in Figure 9-4,2006 Barbara C. McNurlin. Published by Pearson Education.,9-33,2006 Barbara C. McNurlin. Published by Pearson Education.,9-34,Systems IntegrationMiddleware cont.,One type of middleware that has gained popularity: Enterprise Application Integration (EAI):Typically use a message broker to transfer data between applicationsAdd a new level of functionality that distinguishes themAllow users to define business processes and make data integration subject to rules that govern those processese.g. a rule might state that data can only move from purchasing to accounts receivable when X has signed off on the purchase,2006 Barbara C. McNurlin. Published by Pearson Education.,9-35,A TELECOMMUNICATIONS FIRM Case Example: Enterprise Application Integration,Processing customer requests for new and updated services = major cost and source of customer dissatisfactionIt has been estimated that 65 percent of new and change orders in the telephone industry have errors that must be corrected after the fact ($)Rather than build a new system, the company looked to EAI to automate the process using three existing systems:The customer relationship management system (which contains the customer information)The ERP system (which retrieves information for the application to validate the request and ensures that the new service is compatible with the customers existing services), and The accounting system (which contains the pricing information),2006 Barbara C. McNurlin. Published by Pearson Education.,9-36,A TELECOMMUNICATIONS FIRMCase Example: Enterprise Application Integration cont.,Therefore resolution = Customer request service at the call center via the CRMCustomers name and address passed onto ERP system, which retrieve necessary infoMission accomplishedDecreased processing costs Errors eliminatedReduced customer churnNo new applications neededExisting applications not altered,2006 Barbara C. McNurlin. Published by Pearson Education.,9-37,Interorganizational System Development,One of the main business trends is the appearance of business ecosystems “groupings” of businesses that work closely togetherSupply Chain Management systems integrate supply chainsThese are now a major trend as they compete against one another on their ability to reduce costs and time across their entire chainsDevelopment of such inter-organizational systems requires teams from the different organizations to work together,2006