Business Data Communications,
Fourth Edition
Chapter 11: Network Management
Learning Objectives
• Describe the five levels of network
management described by the ISO
• List and explain the objectives of network
management
• Define the characteristics of the network
that affect user satisfaction
• Describe cost-effective network
management techniques
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Learning Objectives
• Describe how network management
objectives are met
• Identify the effect that wireless networks
and e-commerce have on network
management
• List and explain the types of network
monitoring software
• Describe the standards used for network
management
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Introduction
• Network managers have a complex role in the
organization
• Must manage voice and data networks, as well
as e-commerce
• Many tasks must be performed to manage the
networks
• Manager is more visible to the users/customers
• Well-defined objectives will provide good
customer service
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Network Management and the ISO
Model
• ISO/IEC 7498-4 defines five areas for
network management
– Performance Management
• Bandwidth
• Processor & memory availability
• Network devices
– Fault Management
• Detects and responds to abnormal conditions
• Software defines normal operations of network
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Network Management and the ISO
Model
• ISO/IEC 7498-4
– Configuration Management
• Hardware and software make-up of network
– Accounting Management
• Charges by IT to other departments for network
use
– Security Management
• Authorized use of the network
• IDs, passwords, firewalls, antivirus software, data
encryption, formal security procedures
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Objectives of Network
Management
• User Satisfaction
– Methods used vary by application
– Performance
• Response time
• Should be consistent for each application
• Communications time
– Time on the communication line
– Processing time between client and server
• Response time affected by many events
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Objectives of Network
Management
• User Satisfaction
– Availability
•
•
•
•
All components available for use when needed
Maintenance schedule should be publicized
Mean Time Between Failures (MTBF)
Mean Time to Repair (MTTR)
– Reliability
• Errors expected
• Stability of hardware and software
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Objectives of Network
Management
• User Satisfaction
– Backup
•
•
•
•
Software and hardware
Disk mirroring – two drives, one controller
Disk duplexing – two drives, two controllers
Hardware backup depends on the device
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Objectives of Network
Management
• User Satisfaction
– Network Uptime
• Patch around the problem
• Replacement
– Modems, PCs, NOT mainframes, FEPs
• Repair
– Depends on the component
– May take a few hours to a few days
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Objectives of Network
Management
• User Satisfaction
– Information Availability
•
•
•
•
Critical to keep users updated on events
Scheduled downtimes
Alternative work schedules
Help desk
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Objectives of Network
Management
• Cost-Effectiveness
– Prior Planning
•
•
•
•
Key to the success of a network project
Volume and type of data must be considered
Plan for expansion of the network
Buying equipment
– Buy only for current needs
– Buy for current and future needs
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Objectives of Network
Management
• Cost-Effectiveness
– Modular Expansion
• Plan for upgrades
to equipment
• Hubs
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Objectives of Network
Management
• Cost-Effectiveness
–Equipment Expansion
• Buy new equipment for each expansion
–Relocation of Equipment
• Reuse clients and servers in other locations
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Meeting the Objectives
• Staffing
– Skills required
• Design and configuration
• Diagnosis (Troubleshooting)
• Documentation
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Meeting the Objectives
• Network Analysis
– Network Statistics
• Performance monitor can gather statistics
• Simulation models
• Workload generator
• Log files
• Transaction mix should be checked
• Circuit utilization can affect performance
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Meeting the Objectives
• Network Analysis
– Network Changes
• Tuning
– Changes to the network based on the statistics
gathered
• Can change transmission speeds, buffer
sizes
• Change network configuration
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Network Management for Wireless
Networks and e-Commerce
• Wireless Networks
– Managers must know the technology
– Videoconferencing, data archiving, data
mirroring
– Connecting PDAs and laptop computers to
the LAN
– Bandwidth, security, design issues
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Network Management for Wireless
Networks and e-Commerce
• Network Traffic Volume
– High volume caused by e-commerce
– Corporate portal is now important to business
– May slow system response
– Bandwidth may need to be increased
– Must monitor network closely
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Network Management for Wireless
Networks and e-Commerce
• Internet Network Monitoring Tools
– Transaction Monitoring
• End-to-end response time
• Dummy transaction created
– Network Performance Monitoring
• Service level agreements with ISP
– Live-visitor site monitoring
– Human-response monitoring
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General Network Monitoring
Tools
• Classes of Network Monitoring Software
– Device management software
• Monitors specific devices
– Enterprise management software
• Monitors entire system
– Application management software
• Monitors specific applications
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General Network Monitoring
Tools
• Network Management Protocols
– Simple Network Management Protocol
(SNMP)
• Collects and reports data on network performance
• Data stored in management information base
(MIB)
• Security is a problem
• Remote monitoring (RMON) extension
– Stores data at a remote site, rather than a central server
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General Network Monitoring
Tools
• Network Management Protocols
– Common Management Interface Protocol
(CMIP)
•
•
•
•
•
ISO standard
Newer than SNMP
More complete monitoring information
Better security
Major changes needed to an SNMP system to
implement CMIP, so it has not been done
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Summary
• Network managers
responsible for both voice
and data networks, as
well as e-commerce
• ISO defines five levels of
network management
• User satisfaction is
viewed in terms of
response time, equipment
availability, network
reliability, and information
• Cost-effectiveness is
accomplished through
prior planning
Chapter 11: Network Management
• Staffing and network
analysis can be used to
achieve the network
managers goals
• Network tuning is used to
improve performance
• Network performance for
wireless and e-commerce
applications is now needed
• Network monitoring tools
allow the manager to keep
track of how the network is
performing
• SNMP was originally used,
CMIP is newer
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Summary (Continued)
• Staffing and network analysis can be used to
achieve the network managers goals
• Network tuning is used to improve performance
• Network performance for wireless and ecommerce applications is now needed
• Network monitoring tools allow the manager to
keep track of how the network is performing
• SNMP was originally used, CMIP is newer
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