1. 12
Building and Maintaining
Information Systems

2. Table 12.1 Microsoft Programs Software for a New Release

3. Table 12.1 Microsoft Programs Software for a New Release
CUSTOMER
Customers who purchase Microsoft’s software
Microsoft itself, because it must create a basis for new releases and because the software reflects its strategy

4. Table 12.1 Microsoft Programs Software for a New Release
PRODUCT
New release of a software product

5. Table 12.1 Microsoft Programs Software for a New Release
BUSINESS PROCESS
Major steps:
Identify features customers want and features Microsoft wants for strategic reasons
Decide which features to include in a release
Divide the work among small teams and break each team’s work into three phases
Program and test features in each module
Performs a daily build to make sure all parts of the product work together
Decide which features to delay to subsequent releases
Test the entire release
Package and distribute the new release
Rationale:
Produce releases that combine what the customers want and what Microsoft wants to produce
Maintain creativity and responsiblity by assigning subprojects to small teams
Maintain control and compatibilty by doing a daily build

6. Table 12.1 Microsoft Programs Software for a New Release
PARTICIPANTS
Programmers and testers
INFORMATION
Features to be included in the release
Programs
Examples for testing
Project plan
TECHNOLOGY
(Not mentioned in the case)
Programming languages
Debugging techniques
Computers that run the programs

7. Figure 12.1 Costs in design errors detected at different times

8. Figure 12.2 Links between the four phases of an information system

9. OPERATION AND MAINTENANCE
Table 12.2 Common Issues and Problems in Each Phase of an Information System
INITIATION
Can we agree on the purposes and goals of the proposed system?
Are the requirements unnecessarily elaborate and expensive?
DEVELOPMENT
Can we assure that the system genuinely solves the user’s problems?
Can we assure that users will participate effectively in the design process?
IMPLEMENTATION
Can we convert effectively and painlessly from the old system to the new system?
Can we solve political issues related to changes in power relationships?
OPERATION AND MAINTENANCE
Can we keep system performance and uptime at acceptable levels?
Can we correct bugs and enhance the system to keep it focused on current business problems?

10. Table 12.3 Differences between Four System Life Cycles
TRADITIONAL SYSTEM LIFE CYCLE
Issue addressed: Control
Summary: Go through a fixed sequence of steps with signoffs after each step and careful documents.
PROTOTYPE
Issue addressed: Knowledge
Summary: Quickly devellop a working model of the system; use the model to gain experience and decide how the final syatem should operate.
APPLICATION PACKAGES
Issue addressed: Resources and timing
Summary: Purchase an existing information system from a vendor; customize the system if necessary.
Issue addressed: Responsiveness
Summary: Provide tools and support that make it practical for end users to develop their own information systems.

11. Box 12.1 The capability maturity model
Level 1- INITIAL
Processes are ad hoc and sometimes chaotic. Because few processes are defined, successful projects often depend on heroic individual effort.
Level 2- REPEATABLE
Basic project management processes are used to track cost, schedule, and functionality. The discipline exists to repeat previous success with similar projects.
Level 3- DEFINED
Both 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- MANAGED
Detailed 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- OPTIMIZING
Continuous process improvement is facilitated by quantitative feedback from the process and by doing pilot studies of innovative ideas and technologies.

12. Figure 12.3 Steps in the development phase of the traditional system life cycle

13. Figure 12.4 Steps in the implementation phase of the traditional system life cycle

14. Table 12.4 Steps and Deliverables in the Traditional System Life Cycle
INITIATION
Feasibility study
Degree of user participation- High
Key deliverable, plan, or document- Functional specification
Key Participants- User representatives, management, and technical staff
Project planning
Degree of user participation - Medium
Key deliverable, plan, or document - Project plan
Key Participants deliverable, plan, or document - User representatives, management, and technical staff

15. Table 12.4 Steps and Deliverables in the Traditional System Life Cycle
DEVELOPMENT
Detailed requirements analysis
Degree of user participation - High
Key deliverable, plan, or document - External specification
Key Participants- User representatives, management, and technical staff
Internal system design
Degree of user participation - None
Key deliverable, plan, or document - Internal specification
Key Participants- Programmers and technical staff
Hardware acquisition and installation
Key deliverable, plan, or document - Hardware plan Hardware operational
Key Participants- Technical staff
Programming
Key deliverable, plan, or document - Individual programs debugged
Key Participants- Programmers
Documentation
Degree of user participation- Medium
Key deliverable, plan, or document - User and programmer documentation
Key Participants- Technical staff and users
System testing
Degree of user participation - Medium
Key deliverable, plan, or document - Test plan Completed system test
Key Participants- Programmers and users

16. Table 12.4 Steps and Deliverables in the Traditional System Life Cycle
IMPLEMENTATION
Implementation planning
Degree of user participation - High
Key deliverable, plan, or document - Implementation plan
Key Participants- Training staff, users, and management
Training
Key deliverable, plan, or document - Training materials
Key Participants- Trainers and users
Conversion
Key deliverable, plan, or document - System in use
Key Participants- Users and project team
Acceptance testing
Key deliverable, plan, or document - System accepted
Postimplementation audit
Key deliverable, plan, or document - Audit report
Key Participants- Users and management

17. Table 12.4 Steps and Deliverables in the Traditional System Life Cycle
OPERATION AND MAINTENANCE
Ongoing operation and support
Degree of user participation - Low
Key deliverable, plan, or document - Operations manual
Key Participants- Technical staff
Key deliverable, plan, or document - Usage statistics
Key Participants- Technical staff and users
Degree of user participation - High
Key deliverable, plan, or document - Enhancement requests and bug fix requests
Maintenance
Degree of user participation - Medium
Key deliverable, plan, or document - Maintenance
Absorption or termination
Degree of user participation - ======
Key deliverable, plan, or document - ======
Key Participants- ======

18. Table 12.5 System Life Cycle Based on a Prototype
INITIATION
Users and developers agree to develop a prototype because they need experience with a working model before designing a final system.
DEVELOPMENT
Working iteratively with users, a prototype is developed and improved. Later, decide whether to complete the prototype or switch to a traditional life cycle.
IMPLEMENTATION
Accomplish parts of implementation along with development as users work with the prototype system. Dispel skepticism about whether the system will meet users’ needs.
OPERATION AND MAINTENANCE
May be similar to a traditional life cycle. May require less maintenance because the system fits users’ needs more accurately. May require more maintenance because the system is not constructed as well.

19. Figure 12.5 Using a prototype approach

20. Figure 12.6 Creating a data input form
(b)

21. Figure 12.7 Example of a commercial application package

22. Table 12.6 System Life Cycle for Acquiring an Application Package
INITIATION
May start with user’s or manager’s recognition of a business problem or with a sales call from a vendor.
DEVELOPMENT
The vendor develops the software, although the purchase still performs some typical development activities, such as determining detailed requirements. Development may include customization of the software and user documentation.
IMPLEMENTATION
Implementation starts by deciding exactly how the package will be used. It often relies on the vendor’s staff because they have the greatest knowledge of the system.
OPERATION AND MAINTENANCE
Operation occurs as it would with a traditional life cycle. Maintenance is different because the vendor maintains the software based on requests from customers and demands of the market.

23. Box 12.2 Selecting an application package
APPLICATION FEATURES
completeness
quality of reports
ease of use
documentation
TECHNICAL FEATURES
use of DBMS
transportability
expandability
VENDOR COMPARISON
financial strength
management strength
committment to product
ECONOMIC COMPARISON
purchase price
maintenance contract
consulting charges
conversion cost
Total weighted score
WEIGHT
2.5
1.0
2.3
2.8
0.8
1.2
2.0
1.3
2.6
1.5
0.6
SCORE
WEIGHTED SCORE

24. Figure 12.8 Vendor responsibilties for application packages

25. Figure 12.9 A tool for end-user devlopment

26. Table 12.7 System Life Cycle for End-User Development
INITIATION
Because the user will develop the information system, a formal functional specification is unnecessary.
DEVELOPMENT
The user develops the system using tools that do not require a professional level of programming knowledge. Information systems that are critical to the company or have many users require more extensive testing, documentation, and usage procedures.
IMPLEMENTATION
Implementation is simplified because the developer is the user.
OPERATION AND MAINTENANCE
End users are responsible. Long-term maintenance and technical quality become larger issues because the end users have other work to do and are not professional programmers.

27. Figure 12.10 Roles in end-user development

28. Table 12.8 Common Approaches to Issues in End-User Computing
HARDWARE SELECTION AND MAINTENANCE
The IS staff selects the types of harware that can be purchased and maintains the hardware.
SOFTWARE SELECTION
The IS staff selects the the spreadsheet software and other end-user software that can be purchased and used.
TRAINING
The IS staff provides training for end users on selected hardware and software.
DATA AVAILABILITY
End users control their own data and share data using LANs. Corporate data are downloaded from central computers.
DATA SECURITY
Limit access to only the data users need.
SYSTEMS ANALYSIS
Help end users with systems analysis and design where necessary. Provide help lines and other types of support.

29. Table 12.9 Advantages and Disadvantages of Four System Life Cycles
Traditional system life cycle
Prototype
Application package
End-user development