From owner-freebsd-net  Mon Apr 16 18:29:18 2001
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Date: Mon, 16 Apr 2001 21:28:55 -0400 (EDT)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
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To: Kris Kennaway <kris@obsecurity.org>
Cc: freebsd-security@FreeBSD.ORG, net@FreeBSD.ORG
Subject: Re: non-random IP IDs
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<<On Mon, 16 Apr 2001 12:50:53 -0700, Kris Kennaway <kris@obsecurity.org> said:

> Surely that can't work since the purpose of that field is for received
> packet ordering

No.  The IP ID is effectively a nonce with respect to the receiving
system.  The only requirement is that IDs not be repeated while any
packet with the same (source, dest) pair is still in the network.
This is in practice impossible, so as with TCP we can simply pretend
that all packets disappear after 60 seconds.

Having said that, on the whole I think this whole idea is utterly
pointless.

-GAWollman


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