Session 5 - Systems analysis and design.ppt
- 1. Management Information Systems MANAGING THE DIGITAL FIRM, 12TH EDITION SYSTEMS ANALYSIS AND DESIGN
- 2. Management Information Systems • Structural organizational changes enabled by IT 1. Automation • Increases efficiency • Replaces manual tasks 2. Rationalization of procedures • Streamlines standard operating procedures • Often found in programs for making continuous quality improvements – Total quality management (TQM) – Six sigma Systems as Planned Organizational Change CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 2
- 3. Management Information Systems • Structural organizational changes enabled by IT 3. Business process redesign • Analyze, simplify, and redesign business processes • Reorganize workflow, combine steps, eliminate repetition 4. Paradigm shifts • Rethink nature of business • Define new business model • Change nature of organization Systems as Planned Organizational Change CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 3
- 4. Management Information Systems Systems as Planned Organizational Change ORGANIZATIONAL CHANGE CARRIES RISKS AND REWARDS The most common forms of organizational change are automation and rationalization. These relatively slow-moving and slow-changing strategies present modest returns but little risk. Faster and more comprehensive change— such as redesign and paradigm shifts—carries high rewards but offers substantial chances of failure. FIGURE 13-1 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 4
- 5. Management Information Systems • Business process management (BPM) – Variety of tools, methodologies to analyze, design, optimize processes – Used by firms to manage business process redesign • Steps in BPM 1.Identify processes for change 2.Analyze existing processes 3.Design the new process 4.Implement the new process 5.Continuous measurement Systems as Planned Organizational Change CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 5
- 6. Management Information Systems Systems as Planned Organizational Change AS-IS BUSINESS PROCESS FOR PURCHASING A BOOK FROM A PHYSICAL BOOKSTORE Purchasing a book from a physical bookstore requires many steps to be performed by both the seller and the customer. FIGURE 13-2 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 6
- 7. Management Information Systems Systems as Planned Organizational Change REDESIGNED PROCESS FOR PURCHASING A BOOK ONLINE Using Internet technology makes it possible to redesign the process for purchasing a book so that it requires fewer steps and consumes fewer resources. FIGURE 13-3 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 7
- 8. Management Information Systems • Variety of tools for BPM, to – Identify and document existing processes • Identify inefficiencies – Create models of improved processes – Capture and enforce business rules for performing processes – Integrate existing systems to support process improvements – Verify that new processes have improved – Measure impact of process changes on key business performance indicators Systems as Planned Organizational Change CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 8
- 9. Management Information Systems • Systems development: – Activities that go into producing an information system solution to an organizational problem or opportunity 1.Systems analysis 2.Systems design 3.Programming 4.Testing 5.Conversion 6.Production and maintenance Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 9
- 10. Management Information Systems Overview of Systems Development THE SYSTEMS DEVELOPMENT PROCESS Building a system can be broken down into six core activities. FIGURE 13-4 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 10
- 11. Management Information Systems • Systems analysis – Analysis of problem to be solved by new system • Defining the problem and identifying causes • Specifying solutions – Systems proposal report identifies and examines alternative solutions • Identifying information requirements – Includes feasibility study • Is solution feasible and good investment? • Is required technology, skill available? Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 11
- 12. Management Information Systems • System analysis (cont.) – Establishing information requirements • Who needs what information, where, when, and how • Define objectives of new/modified system • Detail the functions new system must perform – Faulty requirements analysis is leading cause of systems failure and high systems development cost Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 12
- 13. Management Information Systems • Systems design – Describes system specifications that will deliver functions identified during systems analysis – Should address all managerial, organizational, and technological components of system solution – Role of end users • User information requirements drive system building • Users must have sufficient control over design process to ensure system reflects their business priorities and information needs • Insufficient user involvement in design effort is major cause of system failure Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 13
- 14. Management Information Systems Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 14 OUTPUT Medium Content Timing INPUT Origins Flow Data entry USER INTERFACE Simplicity Efficiency Logic Feedback Errors DATABASE DESIGN Logical data model Volume and speed requirements File organization and design Record specifications PROCESSING Computations Program modules Required reports Timing of outputs MANUAL PROCEDURES What activities Who performs them When How Where CONTROLS Input controls (characters, limit, reasonableness) Processing controls (consistency, record counts) Output controls (totals, samples of output) Procedural controls (passwords, special forms) SECURITY Access controls Catastrophe plans Audit trails DOCUMENTATION Operations documentation Systems documents User documentation CONVERSION Transfer files Initiate new procedures Select testing method Cut over to new system TRAINING Select training techniques Develop training modules Identify training facilities ORGANIZATIONAL CHANGES Task redesign Job redesign Process design Organization structure design Reporting relationships
- 15. Management Information Systems • Programming: – System specifications from design stage are translated into software program code • Testing – Ensures system produces right results – Unit testing: Tests each program in system separately – System testing: Test functioning of system as a whole – Acceptance testing: Makes sure system is ready to be used in production setting – Test plan: All preparations for series of tests Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 15
- 16. Management Information Systems • Conversion – Process of changing from old system to new system – Four main strategies 1. Parallel strategy 2. Direct cutover 3. Pilot study 4. Phased approach – Requires end-user training – Finalization of detailed documentation showing how system works from technical and end-user standpoint Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 16
- 17. Management Information Systems • Production and maintenance – System reviewed to determine if revisions needed – May include post-implementation audit document – Maintenance • Changes in hardware, software, documentation, or procedures to a production system to correct errors, meet new requirements, or improve processing efficiency – 20% debugging, emergency work – 20% changes to hardware, software, data, reporting – 60% of work: User enhancements, improving documentation, recoding for greater processing efficiency Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 17
- 18. Management Information Systems Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 18 SUMMARY OF SYSTEMS DEVELOPMENT ACTIVITIES CORE ACTIVITY DESCRIPTION Systems analysis Identify problem(s) Specify solutions Establish information requirements Systems design Create design specifications Programming Translate design specifications into code Testing Unit test Systems test Acceptance test Conversion Plan conversion Prepare documentation Train users and technical staff Production and maintenance Operate the system Evaluate the system Modify the system
- 19. Management Information Systems • Most prominent methodologies for modeling and designing systems: 1. Structured methodologies 2. Object-oriented development • Structured methodologies – Structured: Techniques are step-by-step, progressive – Process-oriented: Focusing on modeling processes or actions that manipulate data – Separate data from processes Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 19
- 20. Management Information Systems • Data flow diagram: – Primary tool for representing system’s component processes and flow of data between them – Offers logical graphic model of information flow – High-level and lower-level diagrams can be used to break processes down into successive layers of detail • Data dictionary: Defines contents of data flows and data stores • Process specifications: Describe transformation occurring within lowest level of data flow diagrams • Structure chart: Top-down chart, showing each level of design, relationship to other levels, and place in overall design structure Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 20
- 21. Management Information Systems Overview of Systems Development DATA FLOW DIAGRAM FOR MAIL-IN UNIVERSITY REGISTRATION SYSTEM The system has three processes: Verify availability (1.0), Enroll student (2.0), and Confirm registration (3.0). The name and content of each of the data flows appear adjacent to each arrow. There is one external entity in this system: the student. There are two data stores: the student master file and the course file. FIGURE 13-6 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 21
- 22. Management Information Systems Overview of Systems Development HIGH-LEVEL STRUCTURE CHART FOR A PAYROLL SYSTEM This structure chart shows the highest or most abstract level of design for a payroll system, providing an overview of the entire system. FIGURE 13-7 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 22
- 23. Management Information Systems • Object-oriented development – Object is basic unit of systems analysis and design • Object: – Combines data and the processes that operate on those data – Data encapsulated in object can be accessed and modified only by operations, or methods, associated with that object – Object-oriented modeling based on concepts of class and inheritance • Objects belong to a certain class and have features of that class • May inherit structures and behaviors of a more general, ancestor class Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 23
- 24. Management Information Systems Overview of Systems Development CLASS AND INHERITANCE This figure illustrates how classes inherit the common features of their superclass. FIGURE 13-8 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 24
- 25. Management Information Systems • Object-oriented development – More iterative and incremental than traditional structured development • Systems analysis: Interactions between system and users analyzed to identify objects • Design phase: Describes how objects will behave and interact; grouped into classes, subclasses and hierarchies • Implementation: Some classes may be reused from existing library of classes, others created or inherited – Because objects are reusable, object-oriented development can potentially reduce time and cost of development Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 25
- 26. Management Information Systems • Computer-aided software engineering (CASE) – Software tools to automate development and reduce repetitive work, including • Graphics facilities for producing charts and diagrams • Screen and report generators, reporting facilities • Analysis and checking tools • Data dictionaries • Code and documentation generators – Support iterative design by automating revisions and changes and providing prototyping facilities – Require organizational discipline to be used effectively Overview of Systems Development CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 26
- 27. Management Information Systems • Alternative Systems-Building Methods –Traditional systems life-cycle –Prototyping –End-user development –Application software packages –Outsourcing Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 27
- 28. Management Information Systems • Traditional systems lifecycle: – Oldest method for building information systems – Phased approach divides development into formal stages • Follows “waterfall” approach: Tasks in one stage finish before another stage begins – Maintains formal division of labor between end users and information systems specialists – Emphasizes formal specifications and paperwork – Still used for building large complex systems – Can be costly, time-consuming, and inflexible Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 28
- 29. Management Information Systems • Prototyping – Building experimental system rapidly and inexpensively for end users to evaluate – Prototype: Working but preliminary version of information system • Approved prototype serves as template for final system – Steps in prototyping 1. Identify user requirements 2. Develop initial prototype 3. Use prototype 4. Revise and enhance prototype Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 29
- 30. Management Information Systems Alternative Systems Building Approaches THE PROTOTYPING PROCESS The process of developing a prototype can be broken down into four steps. Because a prototype can be developed quickly and inexpensively, systems builders can go through several iterations, repeating steps 3 and 4, to refine and enhance the prototype before arriving at the final operational one. FIGURE 13-9 CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 30
- 31. Management Information Systems • Advantages of prototyping – Useful if some uncertainty in requirements or design solutions – Often used for end-user interface design – More likely to fulfill end-user requirements • Disadvantages – May gloss over essential steps – May not accommodate large quantities of data or large number of users • May not undergo full testing or documentation Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 31
- 32. Management Information Systems • End-user development: – Uses fourth-generation languages to allow end-users to develop systems with little or no help from technical specialists – Fourth generation languages: Less procedural than conventional programming languages • PC software tools • Query languages • Report generators • Graphics languages • Application generators • Application software packages • Very high-level programming languages Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 32
- 33. Management Information Systems • End-user development (cont.): – Advantages: • More rapid completion of projects • High-level of user involvement and satisfaction – Disadvantages: • Not designed for processing-intensive applications • Inadequate management and control, testing, documentation • Loss of control over data – Managing end-user development • Require cost-justification of end-user system projects • Establish hardware, software, and quality standards Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 33
- 34. Management Information Systems • Application software packages – Save time and money – Many offer customization features: • Software can be modified to meet unique requirements without destroying integrity of package software – Evaluation criteria for systems analysis include: • Functions provided by the package, flexibility, user friendliness, hardware and software resources, database requirements, installation and maintenance efforts, documentation, vendor quality, and cost – Request for Proposal (RFP) • Detailed list of questions submitted to packaged-software vendors • Used to evaluate alternative software packages Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 34
- 35. Management Information Systems • Outsourcing – Several types • Cloud and SaaS providers – Subscribing companies use software and computer hardware provided by vendors • External vendors – Hired to design, create software – Domestic outsourcing » Driven by firms need for additional skills, resources, assets – Offshore outsourcing » Driven by cost-savings Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 35
- 36. Management Information Systems • Outsourcing (cont.) – Advantages • Allows organization flexibility in IT needs – Disadvantages • Hidden costs, e.g. – Identifying and selecting vendor – Transitioning to vendor • Opening up proprietary business processes to third party Alternative Systems Building Approaches CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 36
- 37. Management Information Systems • Rapid application development (RAD) – Process of creating workable systems in a very short period of time – Utilizes techniques such as: • Visual programming and other tools for building graphical user interfaces • Iterative prototyping of key system elements • Automation of program code generation • Close teamwork among end users and information systems specialists Application Development for the Digital Firm CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 37
- 38. Management Information Systems • Joint application design (JAD) – Used to accelerate generation of information requirements and to develop initial systems design – Brings end users and information systems specialists together in interactive session to discuss system’s design – Can significantly speed up design phase and involve users at intense level Application Development for the Digital Firm CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 38
- 39. Management Information Systems • Agile development – Focuses on rapid delivery of working software by breaking large project into several small sub-projects – Subprojects • Treated as separate, complete projects • Completed in short periods of time using iteration and continuous feedback – Emphasizes face-to-face communication over written documents, allowing collaboration and faster decision making Application Development for the Digital Firm CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 39
- 40. Management Information Systems • Component-based development – Groups of objects that provide software for common functions (e.g., online ordering) and can be combined to create large-scale business applications – Web services • Reusable software components that use XML and open Internet standards (platform independent) • Enable applications to communicate with no custom programming required to share data and services • Can engage other Web services for more complex transactions • Using platform and device-independent standards can result in significant cost-savings and opportunities for collaboration with other companies Application Development for the Digital Firm CHAPTER 13: BUILDING INFORMATION SYSTEMS © Prentice Hall 2011 40
Editor's Notes
- #3: This slide discusses the first two of four different types of organizational change that information systems can enable. You can ask students to give examples of each type of change within the context of an example of a business, for example, a pizza chain. Ask students to define TQM (makes achieving quality an end in itself) and six sigma (specific measure of quality – 3.4 defects per million). Ask students to evaluate the two methods. Would one be better in some industries or types of businesses over the other method? Which method would be better for a restaurant chain? Which would be better for a clothing manufacturer? Why?
- #4: This slide discusses the third and fourth types of organizational change that information systems can enable. You can ask students to give examples of each type of change within the context of an example of a business; for example, a pizza chain. Or, you can provide examples of change, and ask students to determine what category that change falls into. For example, what type of organizational change is involved when a business implements its first accounting software? For business process redesign, the text gives the example of Ford Motor Company’s which redesigned its accounts payable process so that vendors no longer needed to send invoices which then needed to be reconciled with purchase orders – instead, purchase orders are entered directly into the system. An example of a paradigm shift is Schneider National which changed its business model from being a long-haul trucking and transportation firm to using its information systems to manage logistics for other companies.
- #5: This graphic illustrates the four types of change, identifying them according to the potential return on investment as well as level of risk. What makes automation a low risk? What makes a paradigm shift or redesign a high risk? It is important to note that BPR and paradigm shifts have high failure rates. Ask the students why this is so. (Organizational change is difficult to orchestrate.)
- #6: This slide discusses business process management, a category of tools and techniques that help firms redesign business processes. It discusses the riskiness of business process reengineering, and the need to properly manage it in order for BPR to be effective. Ask students what the importance of each step. For example, why is it important to determine the right business process to change rather than all business processes (some processes may not yield time or cost savings, you could spend too much money trying to improve all processes, and some processes may already be effective.) Give students an example of a business process and ask how the process could be measured. For example, how would you measure the business process of a customer ordering a meal? Of a kitchen preparing and delivering that meal? What about the business process of hiring a new employee? It is important to note that, even with effective process redesign, a majority of reengineering projects do not achieve breakthrough gains because of inadequate change management.
- #7: This slide’s graphic illustrates the process of purchasing a book prior to reengineering, including the steps if a book is not available. It emphasizes the sequential nature of the task. Besides the time taken for this process, what are other disadvantages of this traditional business process?
- #8: This graphic illustrates the book purchasing process after reengineering as an online process. The new process and technology has reduced numerous stages to four or five. What are the elements that have allowed these steps to occur? Which of the four types of organizational change described earlier does this redesigned process most closely resemble – automation, rationalization, redesign, paradigm shift?
- #9: This slide gives an overview of the various types of BPM tools that firms use to redesign business processes. The text discusses the example of American National Insurance Company, which used Pegasystems BPM workflow software to streamline customer service processes across four business groups. BPM built rules to guide service reps through a single view of customer information across multiple systems, eliminating the need to access multiple applications when handling customer requests. This increased workload capacity of the representatives by 192%.
- #10: This slide and the following slides discuss the activities involved in system development – the creation of a new (or improvements to an existing) information system. The activities listed are performed in order – the first two, systems analysis and systems design are preparatory steps for the system. The last four steps translate the design of the system into actuality. It is important to emphasize that an information system is not technology for technology’s sake. It is a solution to a problem or set of problems the organization perceives it is facing – including the problem of an opportunity that requires the use of information systems in order to undertake. What problems with business processes have students encountered or witnessed in their work or educational career that could have been improved with the help of a new or improved information system?
- #11: This graphic illustrates the six core activities of systems building. Ask students why these activities are represented as a circle. The circular nature indicates that systems building is not a linear process that is finished once the system is built. Typically, additional changes and improvements will need to be made to the system or part of the system that will require additional analysis, design, programming, testing, conversion, and maintenance.
- #12: This slide and the next describe the first stage of systems development, systems analysis. The systems analyst first creates a road map of the existing organization and systems. What does this road map consist of? (Identifying primary owners and users of data along with existing hardware and software.) What constitutes a primary owner of data? Ask students how an analyst would determine if a problem existed with existing systems. (He/she would examine documents, work papers, procedures, observe system operations, and interview key users as well as managers). What does it mean that a solution is feasible from a financial standpoint? A technical standpoint? An organizational standpoint?
- #13: This slide continues the discussion about the first stage in systems development, systems analysis. Establishing information requirements is an essential part of analysis. A system designed around the wrong set of requirements will either have to be discarded because of poor performance or will need to undergo major modifications. As the text discusses later in the chapter, user involvement is essential for gathering requirements. Why is this so? If user involvement is central to gathering information requirements, why should technical specialists, such as systems analysts, also be involved in this process?
- #14: This slide describes the second stage of systems development, systems design. The text explains that like houses or buildings, information systems may have many possible designs. Each design represents a unique blend of all technical and organizational components. What makes one design superior to others is the ease and efficiency with which it fulfills user requirements within a specific set of technical, organizational, financial, and time constraints. Given an identical systems analysis, what elements might be different in a system design created by two different systems designers?
- #15: This slide lists the various types of specifications that must be detailed and describe in a systems design. From this it is easy to see how complex designing a system can be, and how many opportunities there are for mistakes to creep in. Problems in any one of these areas could produce a less-than optimal system and losses in efficiency and productivity. Select a few of the specifications here and ask students what types of problems could result from an inadequate definition of that specification.
- #16: This slide describes the third and fourth stages of systems development, programming and testing. Many companies today do not perform their own programming, but purchase software or outsource programming to a vendor. In outsourcing, who would be responsible for the testing, the vendor or the purchasing company? Would any testing be needed when software is purchased as a package? It is important to note that the importance of testing is typically underrated in systems project planning, and the risks resulting from inadequate testing are enormous. Ask students why, if system testing is performed that checks the entire system, would unit testing be important?
- #17: This slide describes the fifth stage of systems development, conversion. Ask students to describe each of the strategies. What would make one approach more appropriate than another? Is there any case in which a direct cutover would be the optimal strategy?
- #18: This slide describes the sixth and final stage of systems development, production and maintenance, and shows that an information system is never “finished.” Situations and business environments always change, and systems have to change along with the business. Of course many businesses do not want to spend the resources to change their systems as required by a changing environment. And for this reason, systems can become dysfunctional, costing the firm money fixing the problems created by an outdated system. Ask students to discuss if any of the types of maintenance work listed here could be eliminated by better analysis and design?
- #19: This slide summarizes the six stages in system development. Ask students what the difference is between information requirements and design specifications.
- #20: This slide identifies the two most prominent methodologies for modeling systems and introduces the core concepts behind a structured methodology. Ask students what a process is or to give an example of a process. What does it mean to “separate data from processes?”
- #21: This slide continues the discussion of the structured methodology, looking at the tools and techniques that it uses to model an information system. An example data flow diagram is shown on the next slide, so it may be helpful to move to that slide to discuss these diagrams. A data dictionary is needed so that system builders know exactly what data is stored and manipulated. Process specifications express the logic that is used when one piece of data is transformed by a process. A structure chart looks at the main function of the system, breaks it down into sub-functions, breaks sub-functions into more detailed sub-functions, until the smallest level of detail is reached. Ask students to give an example of what the smallest level of detail might look like, for example, in a university system managing student grades and reports.
- #22: This graphic is a data flow diagram. Ask students what the rounded boxes represent (processes) and what the square box represents (an external entity). What about the open rectangle and the arrows? Where does the process begin? Ask a student to step through the process of registering a student for a course, noting what data is transferred at each step. It’s always fun to do data flow diagrams as a group because it illustrates how the same process is seen differently by different people.
- #23: This graphic shows a high-level structure chart. Note that this is high-level – and subfunctions exist for the functions “Get inputs,” “Validate inputs,” etc. What might be a subfunction for “Calculate gross pay”?
- #24: This slide introduces the second of the two main system modeling methodologies – object-oriented development. A key concept here is that of class and inheritance. Ask students what a class is – (general category of similar objects) and to describe objects that might be in the same class. For example, what objects might be in the category “Degrees” in a university’s information system?
- #25: This graphic illustrates the concept of class and inheritance in object-oriented development. The Class employee allows subclasses to be created using the “template” or superclass “Employee” and use the processes and properties defined for Employee. Subclasses can use properties of their superclass and also add their own properties. If a subclass “Intern” was added to this chart, what unique properties might it have?
- #26: This slide continues the discussion of object-oriented development, highlighting unique considerations during the systems development process. Ask students to perform some rudimentary systems analysis and design for an information system that managed inventory for a department store. What classes might be created? What properties would they have? What subclasses would there be for one of these classes and what properties would they inherit? It is important to emphasize that object-oriented development can reduce the time and cost of development through reusing objects and classes from one application for other applications.
- #27: CASE tools are software tools to automate development tasks for either of the two methodologies just discussed (structured, object-oriented). What does it mean that organizational discipline must be used to be used effectively? What kinds of gains in productivity can be expected if CASE tools are used properly?
- #28: Structured methodology and object-oriented development describe the structure of the software applications used by information systems. The next slides discuss different ways in which the work by the teams involved in creating this software can be organized. Ask students to evaluate which of these methods, if implemented effectively, they think might produce the highest ROI. Which might be the riskiest?
- #29: This slide describes the first method for building systems, the traditional systems life-cycle. Ask students what the effects of unanticipated user requirements are when using this type of building method. What is the role of end users in this method?
- #30: This slide discusses the second method of systems building, prototyping. It is an explicitly iterative process. The term iterative has been used several times; ask students to describe what this means (steps to build the system can be repeated over and over). What are the benefits of an iterative process? Note that once no more iterations are needed, the prototype becomes the finished specifications for the final application, or may serve as the production version of the application.
- #31: This graphic illustrates the four steps (rectangles) of prototyping. The steps that are repeated are steps 3) Use the prototype and 4) Revise and enhance the prototype. Would this type of system development be appropriate for developing a large, enterprise management system?
- #32: This slide continues the discussion of prototyping, listing the advantages and disadvantages to using this method of building systems. Ask students to explain these advantages and disadvantages. For example, why is prototyping useful if there is uncertainty in requirements? What kinds of essential steps might be glossed over?
- #33: This slide discusses a third alternative method in systems building, end-user development. What does it mean that fourth-generation languages are less “procedural” than conventional programming languages? What is an example of a conventional programming language? Ask students to describe or give an example of each type of fourth generation language category.
- #34: This slide continues the discussion of end-user development. What types of projects might end-user development be most suited for? How might this type of development result in a loss of control over data?
- #35: This slide discusses a fourth alternative in systems building, the use of application software packages. It is important to note that many functions are common to all business organizations—payroll, accounts receivable, or inventory control. Software packages will fulfill the need for many organizations for these types of functions. However, it is still important to perform systems analysis in order to determine your organization’s requirements for a system. Step through and explain (or have students explain) the evaluation criteria for a package. For example, you would want to outline the functions you need from the package and determine whether the software package provides that.
- #36: This slide describes a fifth alternative in systems building, outsourcing. SaaS and cloud computing were introduced in chapter 5. Have students describe these types of outsourcing in their own words. Refer students to the Learning Tracks on outsourcing and cloud computing.
- #37: This slide continues the discussion of outsourcing. It is important to emphasize the amount of work involved in partnering and sharing work with a vendor. It may take anywhere from 3 months to a year to fully transfer work to a vendor. What other types of hidden costs can students identify?
- #38: The next slides discuss application development methods that emphasize providing fast solutions needed in an increasingly digital world. What elements in RAD are similar to building methods already discussed are used in RAD– CASE tools, prototyping, etc.?
- #39: JAD is a second technique for accelerating the systems building process.
- #40: Agile development is a third technique used to accelerate the systems building process. Could all three of the techniques described be used at the same time?
- #41: Component-based development also speeds up system and software building. Web services describe Internet-standards based reusable software components, that can be combined to build more complex applications, such as checking a customer’s credit, procurement, or placing orders.