Chapter 11 Information System Development and Programming Languages

1. Chapter 11 Information System Development and Programming Languages Specially Modified By S. Linkin HCCS 2009

2. Next Chapter 11 Objectives Discuss the importance of project management, feasibility assessment, documentation, data and information gathering techniques, and information systems security during system development List other programming languages and other program development tools Describe various ways to develop Web pages Discuss the purpose of each phase in the system development cycle List the six steps in the program development cycle Differentiate between low-level languages and procedural languages Explain the basic control structures used in designing solutions to programming problems Identify the benefits of object-oriented programming languages and program development tools

3. Next The System Development Life Cycle What is an information system (IS)? Hardware, software, data, people, and procedures that work together to produce quality information System—Set of components that interact to achieve common goal Businesses use many types of systems p. 406

4. Next The System Development Life Cycle What are the phases of the system development cycle? Phase 2. Analysis • Conduct preliminary investigation • Perform detailed analysis activities: • Study current system • Determine user requirements • Recommend solution Phase 1. Planning Phase 3. Design • Review project requests • Prioritize project requests • Allocate resources • Form project development team • Acquire hardware and software, if necessary • Develop details of system Phase 4. Implementation Phase 5. Operating, Support, and Security • Develop programs, if necessary • Install and test new system • Train users • Convert to new system • Perform maintenance activities • Monitor system performance • Assess system security p. 406 Fig. 11-1

5. Next The System Development Life Cycle What are guidelines for system development? Arrange tasks into phases (groups of activities) Involve users (anyone for whom system is being built) Develop clearly defined standards (procedures company expects employees to follow) p. 407

6. Next The System Development Life Cycle Who participates in the system development life cycle? p. 407 Fig. 11-2

7. Next The System Development Life Cycle What is a systems analyst? Responsible for designing and developing information system Users’ primary contact person p. 407

8. Next The System Development Life Cycle What is theproject team? Formed to work on project from beginning to end Consists of users, systems analyst, and other IT professionals Project leader—one member of the team who manages and controls project budget and schedule p. 408

9. Next The System Development Life Cycle • Process of planning, scheduling, and controlling activities during system development cycle • Project leader identifies elements for project What is project management? Goal, objectives, and expectations, collectively called scope Required activities Time estimates for each activity Cost estimates for each activity Order of activities Activities that can take place at same time p. 408

10. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click PERT Chartsbelow Chapter 11 Next The System Development Life Cycle • Popular tool used to plan and schedule time relationships among project activities What is a Gantt chart? p. 409 Fig. 11-3

11. Next The System Development Life Cycle Operational feasibility What is feasibility? Measure of how suitable system development will be to the company Four feasibility tests: Schedule feasibility Economic feasibility (also called cost/benefit feasibility) Technical feasibility p. 409

12. Next The System Development Life Cycle What is documentation? Collection and summarization of data and information Includes reports, diagrams, programs, and other deliverables p. 409

13. Next The System Development Life Cycle • Review documentation • Observe • Survey • Interview • Joint-application design (JAD) session • Research What are six data and information gathering techniques? p. 410 Fig. 11-4

14. Next The System Development Life Cycle What are some reasons to create or modify an information system? To correct problem in existing system To improve existing system Outside group may mandate change Competition can lead to change p. 410

15. Next The System Development Life Cycle • Formal request for new or modified information system • Also called project request What is a request for system services? p. 411 Fig. 11-5

16. Next The System Development Life Cycle What is the planning phase? Begins when steering committee receives project request Steering committee—decision-making body for the company Function of committee: Review and approve project requests Prioritize project requests Allocate resources Form project development team for each approved project p. 413

17. Conduct preliminary investigation, also called feasibility study Perform detailed analysis Next The System Development Life Cycle What is the analysis phase? p. 413

18. Next The System Development Life Cycle • Determine exact nature of problem or improvement and whether it is worth pursuing What is the preliminary investigation? • Findings are presented in feasibility report p. 413 - 414 Fig. 11-6

19. Next The System Development Life Cycle What is detailed analysis? 1. Study how current system works 2. Determine user’s wants, needs, and requirements 3. Recommend solution Sometimes called logical design p. 415

20. Assesses feasibility of each alternative solution Recommends the most feasible solution for the project Presented to steering committee, which decides how to develop system Next The System Development Life Cycle What is the system proposal? p. 415

21. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click Outsourcing below Chapter 11 Next The System Development Life Cycle Horizontal market software—meets needs of many companies What are possible solutions? Buy packaged software—prewritten software available for purchase Vertical market software—designed for particular industry Write own custom software—software developed at user’s request Outsource—have outside source develop software p. 415

22. Next The System Development Life Cycle What is the design phase? Acquire hardware and software Develop all details of new or modified information system p. 416

23. Next The System Development Life Cycle What is needed to acquire new hardware and software? • Identify all hardware and software requirements of new or modified system Identify technicalspecifications Solicit vendor proposals Test and evaluate vendor proposals Make a decision p. 416

24. Vendor quotes price(s) for listed product(s) Identifies product(s) you want Vendor selects product(s) that meet(s) your requirements and then quotes price(s) Less formal method that uses standard form to request information about product or service Next The System Development Life Cycle What are three basic documents used to summarize technical specifications? Request for quotation (RFQ) Request for proposal (RFP) Request for information (RFI) p. 416

25. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click Value-Added Reseller below Chapter 11 Next The System Development Life Cycle • Complete system provided by value-added reseller What is a value-added reseller (VAR)? • Value-added reseller (VAR) purchases products from manufacturer and then resells them, offering additional services with product p. 417 Fig. 11-7

26. Next The System Development Life Cycle • References from vendor • Talk to current users of product • Product demonstrations • Trial version of software • Benchmark testmeasures performance How do systems analysts test software products? p. 417

27. Next The System Development Life Cycle What is a detailed design? Detailed design specifications for components in proposed solution Includes several activities Database design Input and output design Program design p. 418

28. Next The System Development Life Cycle • Sample of input or output that contains actual data What is a mockup? p. 418 Fig. 11-8

29. Next The System Development Life Cycle • Input or output that contains programming-like notations for data items What is a layout chart? p. 419 Fig. 11-9

30. Next The System Development Life Cycle What is a prototype? Working model of proposed system Beginning a prototype too early may lead to problems p. 419

31. Next The System Development Life Cycle • Software tools designed to support activities of system development cycle What is computer-aided software engineering (CASE)? p. 419 Fig. 11-10

32. Next The System Development Life Cycle • Purpose is to construct, or build, new or modified system and then deliver it to users What is the implementation phase? Convert to new system Train users Install and test new system Develop programs p. 420 - 421

33. Next The System Development Life Cycle What are the four types of tests performed by system developers? Unit Test Systems test Verifies each individual program works by itself Verifies all programs in application work together Integration Test Acceptance Test Verifies application works with other applications Verifies the new system works with actual data p. 420

34. Next The System Development Life Cycle • Showing users exactly how they will use new hardware and software in system What istraining? p. 420 - 421 Fig. 11-11

35. Next The System Development Life Cycle • Used to change from old system to new system What are conversion strategies? p. 421

36. Perform maintenance activities Next The System Development Life Cycle Monitor system performance • Provides ongoing assistance after system is implemented What is the operation,support, and security phase? Assess system security p. 422

37. Next The System Development Life Cycle • Summarizes in writing all of the safeguards that are in place to protect a company’s information assets What is a computer security plan? Identify allinformation assets of an organization Identify allsecurity risksthat may cause an informationasset loss For each risk,identify thesafeguards that exist to detect, prevent, and recover from a loss p. 422

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39. Next Programming Languages • Set of instructions that directs computer to perform tasks What is a computer program? • Programming language—used to communicate instructions p. 423 Fig. 11-12

40. Next Programming Languages What are low-level languages and high-level languages? Low-levellanguage High-level language Machine-dependentruns only on one type of computer Often machine-independentcan run on many different types of computers and operating systems Machine and assembly languages are low-level p. 424

41. Next Programming Languages • Only language computer directly recognizes • Uses a series of binary digits (1s and 0s) with a combination of numbers and letters that represent binary digits What is machine language? p. 424 Fig. 11-13

42. Next Programming Languages • Instructions made up of symbolic instruction codes, meaningful abbreviations and codes • Source program contains code to be converted to machine language What is assembly language? p. 424 - 425 Fig. 11-14

43. Next Programming Languages What is a procedural language? Programmer writes instructions that tell computer what to accomplish and how to do it Uses series of English-like words to write instructions Often called third-generation language (3GL) p. 425

44. Next Programming Languages • Program that converts entire source program into machine language before executing it What is a compiler? p. 425 Fig. 11-15

45. Next Programming Languages • Program that translates and executes one program code statement at a time What is an interpreter? • Does not produce object program p. 426 Fig. 11-16

46. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click COBOLbelow Chapter 11 Next Programming Languages • Designed for business applications • English-like statements make code easy to read, write, and maintain • COmmon Business-Oriented Language What is COBOL? p. 426 Fig. 11-17

47. Next Programming Languages • Powerful language originally designed to write system software • Runs most often on Unix operating systems What is C? p. 427 Fig. 11-18

48. Next Programming Languages What is an object-oriented programming (OOP) language? Used to implement object-oriented design Major benefit is ability to reuse and modify existing objects Event-driven—checks for and responds to set of events Java, C++, and C#, are complete object-oriented languages Object is item that contains data and procedures that act on data Event is action to which program responds p. 427

49. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click Java Platformsbelow Chapter 11 Next Programming Languages • Developed by Sun Microsystems • Uses just-in-time (JIT) compiler to convert source code into machine code What is Java? p. 427 - 428 Fig. 11-19

50. Click to view Web Link,click Chapter 11, Click Web Linkfrom left navigation, then click C++ and C#below Chapter 11 Next Programming Languages • Includes all elements of C, plus additional features for working with object-oriented concepts • Used to develop database and Web applications What is C++? What is C#? • Object-oriented programming language based on C++ • Accepted as a standard for Web applications and XML-based Web services p. 428