Troubleshooting Your
Network
Networking for Home and Small Businesses – Chapter 9
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Objectives

Describe the troubleshooting process.

Describe the utilities used to verify TCP/IP
connectivity.

Identify and describe common hardware and
connection issues in wired and wireless networks.

Utilize the troubleshooting process to document
problems and interact with a help desk.
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The Troubleshooting Process
 Identify and describe troubleshooting process
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The Troubleshooting Process
 Gathering Information
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Approaches
• There are several different structured troubleshooting
techniques available, including:
Top-down
Bottom-up
Divide-and-conquer
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Approaches
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Approaches
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Approaches
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The Troubleshooting Process
Describe approaches to troubleshooting
• Trial and Error
• Substitution
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Utilities Used to Verify TCP/IP Connectivity
Detecting Physical problems
•A large proportion of networking problems are related to physical
components or problems with the physical layer.
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Utilities Used to Verify TCP/IP Connectivity
 Identify and describe software utilities for
troubleshooting connectivity -
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Utilities Used to Verify TCP/IP Connectivity
 Identify and describe software utilities for troubleshooting
connectivity -
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Utilities Used to Verify TCP/IP Connectivity
 Identify and describe software utilities for troubleshooting
connectivity -
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Utilities Used to Verify TCP/IP Connectivity
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Utilities Used to Verify TCP/IP Connectivity
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Utilities Used to Verify TCP/IP Connectivity
 Describe and use tracert
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Utilities Used to Verify TCP/IP Connectivity
 Describe and use netstat
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Utilities Used to Verify TCP/IP Connectivity
 Describe and use nslookup
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Hardware and Connection Issues in Wired &
Wireless Networks
 Isolating connectivity issues
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Hardware and Connection Issues in Wired &
Wireless Networks
 Describe the purpose of LED indicators and their
meaning.
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Hardware and Connection Issues in Wired &
Wireless Networks
 Describe connection issues with wired networks.
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Hardware and Connection Issues in Wired &
Wireless Networks
 Identify and describe radio issues with a wireless
network.
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Hardware and Connection Issues in Wired &
Wireless Networks
 Identify and describe association and authentication
issues within a wireless network.
Encryption is the process of altering the data so
that it is not usable by anyone without the proper
encryption key. If encryption is enabled, the
same encryption key must be configured on both
the AP and the client. If the client associates
with the AP but can not send or receive data, the
encryption key may be the issue.
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Hardware and Connection Issues in Wired &
Wireless Networks
 DHCP Issues.
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Hardware and Connection Issues in Wired &
Wireless Networks
 Troubleshooting Integrated Router to ISP connections.
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Utilizing the Troubleshooting Process for
Documentation and Help Desk Interactions
 Describe the importance of documentation
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Utilizing the Troubleshooting Process for
Documentation and Help Desk Interactions
 Using outside sources of help
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Utilizing the Troubleshooting Process for
Documentation and Help Desk Interactions
 Using the Helpdesk
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Summary
 Effective troubleshooting combines instinct, experience, and
structured techniques to identify, locate, and correct network or
computer problems.
 Documentation is essential in effective troubleshooting, and should
contain baseline information about the network.
 A large proportion of networking problems relate to physical
components.
 Many networking problems can be identified with software utilities
such as ping, tracert, and netstat.
 In a network containing both wired and wireless connections, it is
important to isolate the problem to either the wired or wireless
network.
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