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SDLC Phases. Phase 5: Systems Operation and SupportObjectivesProvide maintenance and improvements for the new information systemSupport users and help them obtain the most value from the new system. Chapter 12. Systems Operation and Support . Objectives. Explain how the systems operation and su
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1. PHASE 5
SYSTEMS OPERATION & SUPPORT
Systems Operation and Support SYSTEMS ANALYSIS & DESIGN
2. SDLC Phases Phase 5: Systems Operation and Support
Objectives
Provide maintenance and improvements for the new information system
Support users and help them obtain the most value from the new system
3. Chapter 12 Systems Operation and Support
4. Objectives Explain how the systems operation and support phase relates to the rest of the SDLC
Describe the information center concept and how it supports user needs
Discuss the three main categories of systems maintenance
Describe standard maintenance procedures
5. Objectives Discuss the role of configuration management in systems operation
Describe the process of capacity planning, including workload and performance measurements
Recognize the signs of system obsolescence
6. Introduction The new system must meet user expectations and provide support for business objectives
Systems analysts perform maintenance, and also act as internal consultants to help users obtain the greatest value from the system
The more a system is used, the more features and enhancements are requested, and the more maintenance is required
7. Introduction Chapter topics
Three types of maintenance: corrective, adaptive, and perfective
Support techniques include maintenance teams, configuration management, and maintenance releases
System performance issues
CASE maintenance tools
Recognizing system obsolescence
8. Overview of Systems Support and Maintenance Activities The systems operation and support phase begins when the system becomes operational and ends when the system is replaced
9. Overview of Systems Support and Maintenance Activities After delivering the system, the analyst must perform two tasks
Provide guidance and user training
Formal training sessions
Technical support
Creation of a centralized information center
Perform necessary maintenance
Keep the system operating properly
Increase its value to users
10. Support Activities User training and assistance
Current employees are trained when the new system is introduced
New employees typically are trained by user departments, rather than IS staff
If significant changes take place, the IS group might develop a user training package
Special Help via e-mail or company intranet
Revisions to the user guide
Training manual supplements
Formal training sessions
11. Support Activities Information centers
An information center has three main objectives
To help people use system resources more effectively
To provide answers to technical or operational questions
To make users more productive by teaching them how to meet their own information needs
An information center also is called a help desk
12. Support Activities Information centers
Typical information center tasks
Show a user how to create a data query or report
Demonstrate an advanced system feature
Help a user recover damaged data
Offer tips for better operation
Explain an undocumented software feature
Show a user how to write a macro
Explain how to access the company’s intranet or the Internet
13. Support Activities Typical information centers tasks
Assist a user in developing a simple database
Answer questions about software licensing and upgrades
Provide information about system specifications
Recommend a system solution that integrates data from different locations
An information center also monitors performance and provides support
14. Maintenance Activities The overall cost of a system includes the systems operation and support phase
Costs include fixed operational costs and maintenance activities
Operational costs are relatively constant, while maintenance costs vary over time
High costs when system is implemented
Relatively low costs during system’s useful life
High costs near end of system’s useful life
15. Maintenance Activities Operational costs
Supplies
Equipment rentals
Software leases
Maintenance activities
Changing programs, procedures, or documentation to ensure correct performance
Adapting the system to changing requirements
Making the system operate more efficiently
16. Maintenance Activities Three types of maintenance
Corrective maintenance
To fix errors
Adaptive maintenance
To add new capability and enhancements
Perfective maintenance
To improve efficiency
17. Maintenance Activities Corrective maintenance
Diagnoses and corrects errors in the system
Investigation, analysis, design, and testing are necessary before a solution is implemented
Typically, a user submits a systems request form with supporting evidence, if necessary
Response depends on the priority of the request
All maintenance is logged
18. Maintenance Activities Adaptive maintenance
Adds enhancements to the system
An enhancement is a new feature or capability
Adaptive maintenance often is required in a dynamic business environment
An adaptive maintenance project is like a mini-SDLC, with similar phases and tasks
Can be more difficult than new systems development, because of the constraints of an existing system
19. Maintenance Activities Perfective maintenance
Involves changing an operational system to make it more efficient, reliable, or maintainable
Requests for corrective and adaptive maintenance typically come from users, while requests for perfective maintenance typically come from the IS department
Techniques
Reverse engineering tools aid design analysis
Reengineering tools can be used interactively to correct errors
20. Managing Systems Operation and Support Systems operation requires effective management techniques
Maintenance team
Configuration management
Maintenance releases
21. Managing Systems Operation and Support Maintenance team
Consists of systems analysts and programmers
Systems analysts on maintenance work need
Solid background in information technology
Strong analytical abilities
Solid understanding of business operations
Effective interpersonal and communication skills
Analysis: studying the whole to understand the individual elements
Synthesis: studying the individual elements to understand the overall system
22. Managing Systems Operation and Support Configuration management
Process for controlling changes in system requirements
Usually involves three steps
1. The maintenance request
2. Initial action on the request
3. Final disposition of the request
Objectives of configuration management
Manage different versions of the system
Organize and handle documentation
23. TRADEOFF Should a systems review committee evaluate maintenance and new systems requests separately, or together?
Some say “let the dollars go where they will do the most good, regardless of project type”
Others feel that separate allocations are needed to protect maintenance projects
All projects draw from the same resource pool, but IS groups often are organized into separate teams, and can handle separate projects better
24. A KEY QUESTION At Brightside Insurance Company, you organized the IS group into two units — one for new systems, one for maintenance
Now one of your best people might quit if he is assigned to the maintenance team
Should you adopt a different policy and allow voluntary assignments?
If you must make the assignments, what criteria should you use?
25. Managing Systems Operation and Support Maintenance releases
With a maintenance release methodology, all noncritical changes are held until they can be implemented at one time
Each new system version is called a release
Numbering systems
Whole number = significant change
After decimal = relatively minor changes or fixes
There are pros and cons to this approach
26. Managing System Performance System performance directly affects users
Centralized operations are easier to measure than complex networks and client/server systems
Various statistics can be used to assess system performance
Capacity planning uses operational data to forecast system capability and future needs
27. Managing System Performance Performance and workload measurement
Response time
Turnaround time
Throughput
28. Managing System Performance Response time
Response time is the overall time between a request for system activity and the delivery of the response
Response time includes three elements
The time necessary to transmit or deliver the request to the system
The time the system needs to process the results
The time it takes to transmit or deliver the results back to the user
Response time is critical for user satisfaction
29. Managing System Performance Turnaround time
Turnaround time measures the efficiency of centralized computer operations, which still are used for certain tasks, such as credit card processing
Turnaround time is the amount of time between the arrival of a request at a computer center and the availability of the output for delivery or transmission
30. Managing System Performance Throughput
Throughput measures the efficiency of the computer itself
Throughput is the time from the input of a request to the central processor until the output is delivered to the system
31. Managing System Performance Capacity planning
Monitors current activity and performance levels
Anticipates future activity
Forecasts the resources needed to provide desired levels of service
In capacity planning you can use a technique called what-if analysis, where you vary one or more elements in a model to see the effect on other elements
32. CASE Tools for System Maintenance A CASE toolkit provides valuable tools for system evaluation and maintenance, such as
A performance monitor
A program analyzer
An interactive debugging analyzer
A restructuring or reengineering tool
Automated documentation tools
Network activity monitors
Workload forecasting software
33. System Obsolescence A system becomes obsolete when its functions are no longer required by users or when the platform becomes outmoded
Typical signs of obsolescence
Adaptive and corrective maintenance is increasing steadily
Operational costs or execution times are increasing rapidly, and routine perfective maintenance does not reverse the trend
34. System Obsolescence Typical signs of obsolescence
A software package is available that provides the same or additional services faster, better, and less expensively
New technology offers a way to perform the same or additional functions more efficiently
Maintenance changes or additions are difficult and expensive to perform
Users request significant new features to support business requirements
35. SOFTWEAR, LIMITED Status report: in mid-December 1999, the payroll package and the ESIP system both are operating successfully and SWL users are satisfied
Corrective maintenance has been performed
Printing and alignment problems were resolved
Adaptive maintenance has been requested
Human resources department wants to develop an annual employee benefits statement, and add additional ESIP deduction choices
36. SOFTWEAR, LIMITED New developments
Pacific Software announced the latest version of its payroll package, which supports integration of payroll and human resources functions
SWL decides to investigate the possibility of a human resources information system (HRIS)
After a preliminary investigation, IS staff recommends that SWL upgrade to the new payroll package and study the development of a company-wide human resources system
37. SOFTWEAR, LIMITED The future
The business environment is changing rapidly
SWL must investigate new information management technology constantly
At this point, the systems development life cycle for SWL begins again