Miscellaneous error reporting

Miscellaneous error reporting
8.1.9 This page will explain what a parameter problem message is and why it occurs.
Devices that process datagrams may not be able to forward a datagram due to an error in the header parameter. This error does not relate to the state of the destination host or network but still prevents the datagram from being processed and delivered, and because of that, the datagram is discarded. In this case, an ICMP type 12 parameter problem message is sent to the source of the datagram. Figure shows the parameter problem message header.
The parameter problem message includes the pointer field in the header. When the code value is 0, the pointer field indicates the octet of the datagram that produced the error.
This page concludes this lesson. The next lesson will describe TCP/IP suite control messages. The first page will provide an overview of control messages.

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