ICMP message delivery

ICMP message delivery

8.1.3 This page will describe the delivery method that is used by ICMP.

ICMP messages are encapsulated into datagrams in the same way any other data is delivered when IP is used. Figure displays the encapsulation of ICMP data within an IP datagram.

Since ICMP messages are transmitted in the same way as any other data, they are subject to the same delivery failures. This creates a scenario where error reports could generate more error reports and cause increased congestion on a network. For this reason, errors created by ICMP messages do not generate their own ICMP messages. Therefore, it is possible to have a datagram delivery error that is never reported back to the sender of the data.

The next page will discuss unreachable networks.

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