Re: [tcpm] 793bis: IP ID

Fernando Gont <fgont@si6networks.com> Wed, 22 January 2020 19:05 UTC

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From: Fernando Gont <fgont@si6networks.com>
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Date: Wed, 22 Jan 2020 16:05:31 -0300
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Subject: Re: [tcpm] 793bis: IP ID
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Hi, Dave,

On 20/12/19 17:37, David Borman wrote:
> Yes, the IPID is only used for doing IP fragment reassembly, so the IPID really doesn’t matter on retransmission when IP fragmentation is not possible.

Some boxes are know to clear DF and fragment packets. That's why some 
implementations have resorted to ensure IP ID uniqueness (or try to), 
even when they send packets with DF=1.

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
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