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14-2. Motivation. If you are in business, you're going to be involved in _____ _____Building good software applications requires involvement by the END USER--the you, friendA PHILOSOPHY--TIWe will reuse before we will buy and we will buy before we will create using 3 or 4GL's. 14-3. Problems with
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1. 14-1 Systems Development
2. 14-2 Motivation If you are in business, you’re going to be involved in _____ _____
Building good software applications requires involvement by the END USER--the you, friend
A PHILOSOPHY--TI
We will reuse before we will buy and we will buy before we will create using 3 or 4GL’s
3. 14-3 Problems with software development It takes too long
It costs too much
It doesn’t deliver the required functionality
Over 70% of SD projects fail!!!
4. 14-4 Concept of Systems Development Life Cycle (SDLC) Definition of SDLC
Stages of SDLC
Traditional versus modern SDLCs
5. 14-5 Systems Development Life Cycle (SDLC) An SDLC represents a set of general categories that show the major steps, over time, of an information systems development project.
6. 14-6 An Eight-Stage SDLC Project initiation
Feasibility study
Logical analysis and design
Acquisition and development
Implementation
Operation
Post-audit evaluation
Maintenance
7. 14-7
8. 14-8 What’s Missing here? Testing--up to 40% of the total development time
your book has nothing to say about it at all--SHAME
We should also note that roughly 80% of ISD budgets are spent on maintenance
This includes fixing bugs
Changing interfaces, structure
Enhancements
9. 14-9 Project Initiation Functional Manager
Formal planning process
IS organization
10. 14-10 Feasibility Studies Technology
Economics
Organizational factors
Legal, ethical, and other constraints
But not the time-frame for development
11. 14-11 Logical Analysis and Design Determine the system’s functions
How will it accomplish those functions
Logical design
Physical design / technical design
12. 14-12 Logical Design Generic IS functions: input, output, and storage
Modeling tools: DFDs, ERDs
Data Flow Diagrams
Entity-Relation Diagrams
User involvement
13. 14-13 Implementation Parallel conversion
Direct cut-over
The most risky
Pilot conversion
May be implemented in a subset of locations
Phased
14. 14-14 Traditional versus Modern SDLC Minimal overhead
Flexibility and responsiveness
Concurrent tasks
Focused analysis
15. 14-15 Methods for Complex or Quickly Needed Systems Prototyping
Rapid Application Development (RAD)
Object-Oriented Development (OOD)
End-User Development (EUD)
16. 14-16 Prototyping The prototyping approach to systems development is, in many ways, the very opposite of an old-style SDLC. The focus of prototyping is to develop something quickly from the users’ initial set of requirements. Then refine and extend it based on the users’ requirements, which are identified by using the prototype.
17. 14-17 More on Prototyping May use a 4GL to prototype
Best when user requirements are not well-defined
Helps developers get the user interface right
Finalized code is then written in a 3GL--C, C++, etc.
Also known as EVOLUTIONARY development
18. 14-18 Rapid Application Development Rapid Application Development (RAD) methodologies and tools have capabilities to meet the demands of the new environment.
19. 14-19 Components and Capabilities of RAD Uses a 4GL--Visual Basic, PowerBuilder, Delphi
Uses a client-server architecture
GUI development environment
the ability to drag-and -drop components into an application
Reusable components
Code generator
Programming language
20. 14-20 Object-Oriented Development Encapsulation
Inheritance
Plug-and-play landscape
Polymorphism--the ability to send the same message to several different receivers and have the message trigger the correct service
21. 14-21 Object-Oriented Development Procedures (functions, subroutines) are called methods
Generic objects are called classes
Specific objects are called instances
22. 14-22 Object-Oriented DevelopmentBenefits Reduces complexity of systems development
Systems are quicker and easier to build and maintain
Improves productivity
Objects may be reused
23. 14-23 Object-Oriented DevelopmentBenefits Systems are more flexible
Allows analysis to think in real world terms
Ideal for Web development
24. 14-24 End-User DevelopmentTrends END-USERS ARE DOING MORE SOFTWARE DEVELOPMENT
Increasingly powerful desktop hardware
Declining hardware costs
Increasingly diverse software capabilities
Increasingly computer-literate population
Backlog of centralized IS projects (36 or more months)
25. 14-25 More End-User Development(EUD) Trends Development speed
Business orientation
Small applications
Control
Apparent cost savings
26. 14-26
27. 14-27 EUD Problems Additional spending
Hardware
Software
Training
Support
Neglecting other duties
28. 14-28 More EUD Problems Limited managerial technical skills
Documentation
Security
29. 14-29 EUD Solutions Auditing EUD programs
Dividing computing responsibilities
30. 14-30 Third Party Software Application software packages
Outsourcing
Enterprise software
SAP, Computer Associates, Oracle,
31. 14-31 Who is the largest software company? IBM?
Microsoft?
SAP?
Oracle?
Computer Associates?
Novell?
You will have to know for the exam
32. 14-32 Internet Development Web pages are primarily coded in HTML
Java scripts are used to produce the animation boxes
33. 14-33 Development Tools Database creation tools
4GL’s
CASE tools--broadest support for the SDLC (the systems development process)
Computer-Aided Software Engineering (Sterling’s COOL GEN series)
Object-oriented tools like FORTE, Optima
Testing tools
Documentation tools
34. 14-34 Desirable outcomes and implementation issues
Managerial considerations Acquiring New Systems--Outline
35. 14-35 Desirable Outcomes and Implementation Issues On-time
On-budget
Full functionality
User acceptance
Favorable costs-to-benefits ratio
36. 14-36 More Desirable Outcomes and Implementation Issues Low maintenance
Scalability
Integration with other systems
Minimal negative cross impacts
Reusability
37. 14-37 Capability Maturity Model Developed by the SEI at Carnegie Mellon
A way to assess the maturity of any software process, such as development
Initial
Repeatable
Defined
Managed
Optimizing
38. 14-38 Management Considerations Traditional SDLC methodology
Prototyping
Rapid Application Development (RAD)
Object-Oriented Development (OOD)
End-User Development (EUD)
Purchasing or outsourcing
39. 14-39 System Development Issues Internet and intranet applications
JAVA
CASE tools
IS-9000
Project planning
40. 14-40 Managerial Issues Importance
Building inter-organizational and international information systems
Ethical and legal issues
User involvement
Traditional approaches vs. prototyping
41. 14-41 Managerial Issues Tool use by developers
Quality assurance vs. schedules
Behavior problems
Perpetual development