ICMPv4 messages
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... response. RFC 792std5 defines the "original datagram" field for ICMPv4
messages. In RFC 792std5, the "original datagram" field includes the IP
header ...
... In order to solve this problem, this memo introduces an 8-bit length
attribute to the following ICMPv4 messages.
- Destination ...
... octets, whose value was previously required to be zero.
For ICMPv4 messages, the length attribute represents 32-bit words.
When the length attribute is specified, the "original datagram ...
... 32-bit boundary. Because the
sixth octet of each of the impacted ICMPv4 messages was reserved for
future use, this octet was selected as the location of the length
attribute in ICMPv4 ...