Internet Control

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Chapter 9
Internet Control Message Protocol (ICMP)
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CONTENTS

• TYPES OF MESSAGES
• MESSAGE FORMAT
• ERROR REPORTING
• QUERY
• CHECKSUM
• ICMP PACKAGE

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Figure 9-1
Position of ICMP in the network layer
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Figure 9-2
Encapsulation of ICMP packet
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TYPES OF MESSAGES
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Figure 9-3
ICMP messages
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MESSAGE FORMAT
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Figure 9-4
General format of ICMP messages
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ERROR REPORTING
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(No Transcript)
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Figure 9-5
Error-reporting messages
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Figure 9-6
Contents of data field for error messages
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Figure 9-7
Destination-unreachable format
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Figure 9-8
Source-quench format
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(No Transcript)
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Figure 9-9
Time-exceeded message format
Code 0 Time to liveCode 1 Fragmentation
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Figure 9-10
Parameter-problem message format
Code 0 Main header problemCode 1 Problem in
the option field
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Figure 9-11
Redirection concept
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Figure 9-12
Redirection message format
Code 0 Network specificCode 1 Host
specificCode 2 Network specific (specified
service) Code 3 Host specific (specified
service)
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QUERY
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Figure 9-13
Query messages
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Figure 9-14
Echo-request and echo-reply message format
Ping command can use theses messages.
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Figure 9-15
Timestamp-request and timestamp-reply message
format
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Given the following information
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We can calculate
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Given the actual one-way time,
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We have
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Figure 9-16
Mask-request and mask-reply message format
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Figure 9-17
Router solicitation message format
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Figure 9-18
Router advertisement message format
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CHECKSUM
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Figure 9-19
Example of checksum calculation
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ICMP PACKAGE
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Figure 9-20
ICMP package