ICMP Echo Reply

From Free net encyclopedia

The Echo Reply is an ICMP message generated in response to an ICMP Echo Request message, and is mandatory for all hosts and routers.

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Type = 0

Code = 0

Header Checksum

</table>

Identifier

<p align="center">Sequence Number

</table>

• Type and Code must be set to 0.
• The Identifier and Sequence Number can be used by the client to manage which Echo Requests are associated with the Echo Replies.
• The Data received by the Echo Request must be entirely included in the Echo Reply.

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