Previous: F.2 TCP Segment Header Appendix F Selected TCP/IP Headers F.3 ICMP Parameter Problem Message Header This description is taken from pages 8 and 9 of RFC 792, Internet Control Me
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Message Header
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Header
Appendix F Selected TCP/IP Headers
F.3 ICMP Parameter Problem Message Header
This description is taken from pages 8 and 9 of RFC 792, Internet Control Message Protocol, by Jon Postel,
Information Sciences Institute, University of Southern California
Parameter Problem Message
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Code | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Pointer | unused | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Internet Header + 64 bits of Original Data Datagram | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type
12
Code
0 = pointer indicates the error
Checksum
The checksum is the 16-bit ones's complement of the one's
complement sum of the ICMP message starting with the ICMP Type For computing the checksum , the checksum field should be zero Pointer
If code = 0, identifies the octet where an error was detected Internet Header + 64 bits of Data Datagram
The internet header plus the first 64 bits of the datagram that elicited this error response
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Header
TCP/IP Network Administration
F.2 TCP Segment Header Book Index
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