chapter 12 securing and supporting the system 1. phase description systems operation, support, and...
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CHAPTER 12SECURING AND
SUPPORTING THE SYSTEM
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Phase Description
• Systems Operation, Support, and Security is the final phase in the systems development life cycle• You will support and maintain the system,
handle security issues, protect the integrity of the system and its data, and be alert to any signs of obsolescence• The deliverable for this phase is an
operational system that is properly maintained, supported, and secured
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Chapter Objectives • Explain the systems support and security phase• Describe user support activities, including user
training and help desks• Define the four types of maintenance• Explain various techniques for managing
systems maintenance and support• Describe techniques for measuring, managing,
and planning system performance• Explain risk management concepts• Assess system security at six levels: physical
security, network security, application security, file security, user security, and procedural security
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Chapter Objectives
•Describe backup and disaster recovery•List factors indicating that a system has
reached the end of its useful life•Assess future challenges and
opportunities for IT professionals•Develop a strategic plan for career
advancement and strong IT credentials
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Introduction
• Managing systems support and security involves three main concerns: user expectations, system performance, and security requirements• Successful, robust systems often need the
most support• In most organizations, more than half of
all IT department effort goes into supporting existing systems
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Overview
•The systems operation, support, and security phase begins when a system becomes operational and continues until the system reaches the end of its useful life
•After delivering the system, the IT team focuses on support and maintenance tasks
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User Support
User Training– Additionally, new employees must be trained
on the company’s information systems–User training package– Training users about system changes is similar
to initial training– Objective is to show users how the system can
help them perform their jobs
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User Support•Help Desks
▫Helpdesk is a centralized resource staff by IT professionals who provides users with he support they need to do their jobs
▫Enhance productivity and improve utilization of a company’s information resources
▫The help desk is a central contact point for all IT maintenance activities
▫Can utilize many types of automated support
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Maintenance Tasks
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Maintenance Tasks•Four classification of maintenance
activities:• Corrective Maintenance
▫Diagnoses and corrects errors in an operational system
▫Respond to errors in various ways, depending on nature
▫Worst-case situation is a system failure▫When the system is operational again, the
maintenance team determines the cause, analyzes the problem, and designs a permanent solution
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Maintenance Tasks
•Adaptive Maintenance▫Adds enhancements to an operational
system and makes the system easier to use▫The procedure for minor adaptive
maintenance is similar to routine corrective maintenance
▫Can be more difficult than new systems development because the enhancements must work within the constraints of an existing system
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Maintenance Tasks• Perfective Maintenance– Involves changing an operational system to
make it more efficient, reliable and maintainable–Cost-effective during the middle of the system’s
operational life–Programs that need a large number of
maintenance changes usually are good candidates for reengineering
–The more a program changes, the more likely it is to become inefficient and difficult to maintain
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Maintenance Tasks
•Preventive Maintenance▫Requires analysis of areas where trouble is
likely to occur▫IT department normally initiates preventive
maintenance▫Often results in increased user satisfaction,
decreased downtime, and reduced TCO▫Sometimes does not receive the high
priority that it deserves
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Maintenance Management
• The Maintenance Team▫System administrator▫Systems analysts▫Programmers▫Organizational issues
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Maintenance Management
•Maintenance Requests▫Involve a series of steps▫All work must be covered by a specific
request Initial determination The systems review committee Task completion User notification
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Maintenance Management
•Establishing Priorities▫In many companies, systems review
committee separates maintenance requests from new systems development requests
▫Some IT managers believe that evaluating all projects together leads to the best possible decisions
▫Object is to have a procedure that balances new development and necessary maintenance work
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Maintenance Management• Configuration Management
▫ Configuration management (CM) /change control (CC) is a process for controlling changes in the system requirements during software development
▫As enterprise-wide information systems grow more complex, configuration management becomes critical
▫Also helps to organize and handle documentation
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Maintenance Management• Maintenance Releases
▫ Each change is documented and installed as new version of the system
▫A numbering pattern distinguishes the different releases
▫Reduces the documentation burden▫Service packs-software maintenance release
• Version Control▫ Process of tracking system release or versions▫When new version of system is installed, the
prior release is Archived ▫Essential part of system documentation
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Maintenance Management• Baselines
▫Is a formal reference point that measures system characteristics at a specific time
▫Systems analysts use baselines as yardsticks to document features and performance during the systems development process
▫Functional baseline-is the configuration of the system documented at the beginning of the project
▫Allocated baseline-documents the system at the end of the design phase and identifies any changes sine the functional baseline
▫Product baseline-describes the system at the beginning of system operation.
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System Performance Management
• Fault Management▫Detect and resolve operational problems as
quickly as possible▫The more complex the system, the more difficult
it can be to analyze symptoms and isolate a cause
▫The best strategy is to prevent problems by monitoring system performance and workload
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System Performance Management• Performance and Workload Measurement
▫ Benchmark testing-uses a set of standard tests to evaluate system performance and capacity
▫ Metrics –can monitor the number of transactions processed in a given time period, the number of record accessed and the volume of online data
▫ Network performance metrics: Response time
Is the overall time between a request for system activity and the delivery of the response
Bandwidth and throughput Bandwidth describes the amount of data that the system can transfer
in a fixed time period▫ Kbps (kilobits per second)▫ Mbps (megabits per second)▫ Gbps (gigabits per second)
Throughput-measures actual system performance under specific circumstances and s affected by network load and hardware efficiency.
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System Performance Management• Turnaround time– Measures the time between submitting a request
from information and the fulfillment of the request– 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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System Performance Management• Capacity Planning
▫ Process that monitors current activity and performance levels, anticipates future activity and forecast the resources needed to provide desired levels of service.
▫ What-if analysis-allow you to vary one or more elements in a model in order to measure the effect on other elements
▫ Need detailed information▫ Need an accurate forecast of future business
activities▫ Should develop contingency plans based on input
from users and management
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System Performance Management
• 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 Overview• Security is a vital part of
every computer system• Security protect the
system and keep it safe free from danger and reliable.
• System Security Concepts▫ CIA triangle-three main
element of system security: Confidentiality Integrity Availability
▫ Security policy
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System Security Overview
• Risk Management▫ Absolute security is not a
realistic goal▫ Risk identification -
exploit▫ Risk assessment - risk▫ Risk control
Avoidance, mitigation, transference, acceptance
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System Security Overview
•Attacker Profiles and Attacks▫An attack is a hostile act that targets the
system or the company itself.▫An attack might be launched by a
disgruntled employee, or a hacker who is 10,000 miles away
▫Attackers break into a system to cause damage, steal information, or gain recognition, among other reasons
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Security Levels
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Security Levels• Must consider six separate but interrelated
levels• Physical Security– First level of security concerns the physical
environment– Physical access to a computer represents an
entry point into the system and must be controlled and protected
▫Operations center security▫Servers and desktop computers▫Notebook computers
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Security Levels• Network Security
Network is defined as two or more devices that are connected
Network interface-combination of h/w and s/w that allows the computer to interact with the network
To provide security for network traffic,data can be Encrypted
▫Encrypting network traffic
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Security Levels• Network Security
▫Wireless networks WEP WPA
▫ Private networks▫Virtual private networks
tunnel▫Ports and services
Port scan Denial of service
▫Firewalls▫Network intrusion detection
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Security Levels
•Application Security▫Services▫Hardening▫Application permissions▫Input validation▫Patches and updates▫Software Logs
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Security Levels
•File Security▫encryption▫Permissions
Read a file Write a file Execute a file Read a directory Write a directory
▫User Groups
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Security Levels
• User Security▫User resistance▫Identity management▫Password protection▫Social engineering▫New technologies
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Security Levels
• Procedural Security▫Operational security▫Dumpster diving▫Paper shredders
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Backup and Disaster Recovery
• Backup refers to copying data at prescribed intervals or continuously
• Recovery involves restoring the data and restating the system after an interruption
• Backup Policies▫Backup policy contains detailed instructions
and procedures.▫Should specify:
Backup media Rotation schedule Offsiting
Backup Types Retention periods
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Backup and Disaster Recovery•Business Continuity Issues
▫Test plan▫Business continuity plan (BCP)▫Hot site▫Data replication▫Business insurance
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System Obsolescence• At some point every system becomes obsolete• Systems operation and support continues until a
replacement system is installed• A system become obsolete when it no longer supports user
needs or when he platform become outmoded.• Signs :
▫ The system’s maintenance history indicates that adaptive and corrective maintenance are increasingly steady
▫ Operational costs or execution times are increasingly rapidly, and routine perfective maintenance does not reverse or slow the trend.
▫ A software package is available that provides the same or additional services faster, better and less expensively than the current system
▫ New technology offers a way to perform the same or additional functions more efficiently
▫ Maintenance changes or additions are difficult and expensive to perform
▫ User request significant new features to support business requirements
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Future Challenges and Opportunities
•Strategic planning for IT professionals▫Working backwards from your long-term
goals, you can develop intermediate mile stones and begin to manage your career just as you would manage an IT project
▫Planning a career is not unlike planting a tree that takes several years to reach a certain height
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Future Challenges and Opportunities• IT Credentials and Certification
▫Credentials▫Certification▫In addition to Microsoft, many other IT
industry leaders offer certification, including Cisco, Novell, Oracle, and Sun Microsystems
• Critical thinking skills
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Chapter Summary
• Systems support and security 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
• Systems analysts need the same talents and abilities for maintenance work as they use when developing a new system
• Security is a vital part of every computer system
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Chapter Summary
• All information systems eventually become obsolete• An IT professional should have a strategic
career plan that includes long-term goals and intermediate milestones• An important element of a personal
strategic plan is the acquisition of IT credentials and certifications that document specific knowledge and skills
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Review Questions1. Describe four classification of maintenance and
provide an example of each type.2. What is configuration management and why is
it important?3. What is release methodology?4. What is purpose of version control?5. Explain three main elements of system security.6. What are the six security level?7. List six indications that an information system
is approaching obsolesces.
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