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Re: Question on "identification" field of IP header

Alan Cox <alan@lxorguk.ukuu.org.uk> Fri, 13 December 2002 17:21 UTC

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Subject: Re: Question on "identification" field of IP header
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Ramesh Shankar <RShankar@novell.com>
Cc: end2end <end2end-interest@postel.org>, TCP-IMPL <tcp-impl@grc.nasa.gov>
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On Fri, 2002-12-13 at 14:49, Ramesh Shankar wrote:
> If the "Don't fragment bit" is set in the IP header, what purpose does 
> the "identification" field serve? Why can't I simply put 0 for this 
> field in such a case? I remember coming across some e-mail chain in one 

Linux does this in some situations. At high speed it becomes a real
issue because the ip id reuse time is way way lower than the amount of
time fragments get lost in the network  Checksums should help avoid this
but they are not very strong

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