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PHASE 5SYSTEMS OPERATION & SUPPORT
Systems Operation and Support
SYSTEMS ANALYSIS & DESIGN
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SDLC Phases
Phase 5: Systems Operation and SupportObjectives
Provide maintenance and improvements for the new information system
Support users and help them obtain the most value from the new system
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Chapter 12
Systems Operation and Support
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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Maintenance Activities
Three types of maintenance Corrective maintenance
To fix errors Adaptive maintenance
To add new capability and enhancements Perfective maintenance
To improve efficiency
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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
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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
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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 errorsClick to see Figure 12-7Click to see Figure 12-7
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Managing Systems Operation and Support Systems operation requires effective
management techniques Maintenance team Configuration management Maintenance releases
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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
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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
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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
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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?
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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
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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
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Managing System Performance
Performance and workload measurement Response time Turnaround time Throughput
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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