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Systems Analysis & Design7th Edition
Topic 9
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Chapter Objectives
Explain how the systems operation, support, and security phase relates to the overall system development process
Describe user support activities, including user training and help desks
Discuss the four main types of system maintenanceExplain various techniques for managing systems
operation and support
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Chapter Objectives
Describe techniques for measuring, managing, and planning system performance
Assess system security at five levels: physical security, network security, application security, file security, and user security
Describe backup and disaster recoveryAssess future challenges for IT professionals as
technology reshapes the workplace
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Overview of Systems Support and Maintenance
The systems operation, support, and security begins when a system becomes operational and continues until the system reaches the end of its useful life
After delivering the system, the analyst has two other important tasks: he or she must support users and provide necessary maintenance to keep the system operating properly
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User Support Activities
User Training– Additionally, new
employees must be trained on the company’s information systems
– Training users about system changes is similar to initial training
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User Support Activities
Help Desk– Often called an
information center (IC)– Enhance productivity
and improve utilization of a company’s information resources
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User Support Activities
Help Desk– Might have to perform the following tasks:
• Show a user how to create a data query or report that displays specific business information
• Resolve network access or password problems• Demonstrate an advanced feature of a system or a
commercial package• Help a user recover damaged data
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User Support Activities
Online Chat Support– Interactive support also can be delivered in the
form of an online chat– Blackboard provides a chat room called a Virtual
Classroom, which is an online meeting-place where students can ask questions and interact with an instructor
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Maintenance Activities
The systems operation, support and security phase is an important component of TCO (total cost of ownership) because ongoing maintenance expenses can determine the economic life of a system
Operational costsMaintenance expensesMaintenance activities
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Maintenance Activities
Four types of maintenance task can be identified– Corrective maintenance– Adaptive maintenance– Perfective maintenance– Preventative maintenance
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Maintenance Activities
• Four types of maintenance task can be identified
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Managing Systems Support
Maintenance Team– System administrator– Systems analysts
• Analysis• Synthesis
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Managing Systems Support
Maintenance Team– Programmers
• Applications programmer• Systems programmer• Database programmer• Programmer/analyst
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Managing Systems Support
Managing Maintenance Requests– Involves a number of
steps• Maintenance request
• Initial determination
• Role of the systems review committee
• Completion of the work
• User notification
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Managing Systems Support
Establishing Priorities– In many companies, systems review committee
separates maintenance requests from new systems development requests
– Many IT managers believe that evaluating all projects together leads to the best possible decisions
– Neither approach guarantees an ideal allocation between maintenance and new systems development
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Managing Systems Support
Configuration Management– Configuration management (CM)– As enterprise-wide information systems grow
more complex, configuration management becomes critical
– Most maintenance projects require documentation changes
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Managing Systems Support
Maintenance Releases– Maintenance release methodology– A numbering pattern distinguishes the different
released– Reduces the documentation burden– But new features or upgrades are available less
often– Service packs
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Managing Systems Support
Version Control– Archived – Systems librarian– Companies can
purchase software such as Serena
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Managing Systems Support
Baseline– Systems analysts use baselines as yardsticks to
document features and performance during the systems development process
– Functional baseline– Allocated baseline– Product baseline
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Managing System Performance
Performance and Workload Measurement– Metrics – Response time– Bandwidth and throughput
• Kbps (kilobits per second)
• Mbps (megabits per second)
• Gbps (gigabits per second)
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Managing System Performance
Performance and Workload Measurement– Turnaround time
• The IT department often measures response time, bandwidth, throughput, and turnaround time to evaluate system performance both before and after changes to the system or business information requirements
• Management uses current performance and workload data as input for the capacity planning process
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Managing System Performance
Capacity Planning– What-if analysis– You need detailed information about the number
of transactions; the daily, weekly, or monthly transaction patterns; the number of queries; and the number, type, and size of all generated reports
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Managing System Performance
System Maintenance Tools– Many CASE tools include system evaluation and
maintenance features– In addition to CASE tools, you also can use
spreadsheet and presentation software to calculate trends, perform what-if analyses, and create attractive charts and graphs to display the results
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System Security
Physical Security– First level of security concerns the physical
environment– Computer room– Computer room security
• Biometric scanning systems• Motion sensor
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System Security
Physical Security– Servers and desktop computers
• Keystroke logger• Tamper-evident cases• BIOS-level password• Boot-level password• Power-on password
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System Security
Physical Security– Notebook computers
• Select an operating system that allows secure logons and BIOS-level passwords
• Mark or engrave the computer’s case
• Consider notebook models that have a built-in fingerprint reader
• Universal Security Slot (USS)
• Back up all vital data
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System Security
Physical Security– Notebook computers
• Use tracking software
• While traveling, try to be alert to potential high-risk situations
• Establish stringent password protection policies
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System Security
Network Security– Network– Network interface– Encrypted– Encrypting network traffic
• Unencrypted – plain text
• Public key encryption (PKE)
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System Security
Network Security– Encrypting network traffic
• Public key
• Private key
• Wi-Fi Protected Access (WPA)
• Wired Equivalent Privacy (WEP)
• WPA2
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System Security
Network Security– Private networks
• Private network
– Virtual private networks• Virtual private network
(VPN)
• Tunnel
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System Security
Network Security– Ports and services
• Port
• Destination port
• Service
• Port scans
• Denial of service (DOS)
• Distributed denial of service (DDOS)
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System Security
Network Security– Firewalls
• Firewalls can be configured to detect and respond to DOS attacks, port scans, and other suspicious activity
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System Security
Application Security– Services
• Security hole• Administrator – super-user• Permissions
– Input validation– Patches and updates
• Patches• Third-party software• Automatic update service
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System Security
Application Security– Patches and updates
• Exploits
• Patches
• Third-party software
• Automatic update service
File Security– Permissions– User Groups
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System Security
User Security– Privilege escalation attack– Identity management– Password protection– Social engineering
• Pretexting
– User resistance
Backup and Disaster Recovery
• Backup Policies– Backup policy– Backup media
• Rotation schedule• Offsiting
– Backup Types– Retention periods
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Backup and Disaster Recovery
• Backup Policies
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Backup and Disaster Recovery
• Business Continuity Issues– Test plan– Business continuity plan (BCP)– Hot site– Data replication
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Facing the Future: Challenges and Opportunities
Predictions– It is clear that companies will continue to face
intense competition and global change, especially in the wake of economic, social, and political uncertainty
– Although disruptions will occur, technology advances will spur business growth and productivity
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Facing the Future: Challenges and Opportunities
Predictions– It is interesting to note that some observers, such
as Bill Joy, wonder whether technology is moving so fast that humans will be left behind
– What does seem clear is that the future world of IT must be envisioned, planned, and created by skilled professionals
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Chapter Summary
Systems operation, security, and support covers the entire period from the implementation of an information system until the system no longer is used
A systems analyst’s primary involvement with an operational system is to manage and solve user support requests
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Chapter Summary
Systems analysts need the same talents and abilities for maintenance work as they use when developing a new system
Configuration management is necessary to handle maintenance requests
System performance measurements include response time, bandwidth, throughput, and turnaround time
