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If I have two shells open each pinging the same host, how do the two shells differentiate between the ICMP responses coming back for each shell?

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up vote 12 down vote accepted

The request includes a 2-byte Identifier field, which must match in the reply. This is separate from the Sequence field. You can see it described in RFC 792

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Thanks. it was right between pages 13 and 14. – Peter Jul 9 '12 at 3:41

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