Re: [v6ops] WG Doc? draft-gont-v6ops-ipv6-ehs-packet-drops

Nick Hilliard <nick@foobar.org> Mon, 14 March 2016 18:00 UTC

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Date: Mon, 14 Mar 2016 17:59:52 +0000
From: Nick Hilliard <nick@foobar.org>
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Subject: Re: [v6ops] WG Doc? draft-gont-v6ops-ipv6-ehs-packet-drops
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Tom Herbert wrote:
> From that point of view, the IPv6 flow label "works best" for ECMP
> and so the three tuple hash (addresses and flow label) should be the
> recommended method for ECMP devices to implement.

Tom,

Everyone agrees with this.  The problem is that core and leaf operators
are not in control of flow label generation at the edge, and many
operating systems do not bother to set the flow label.  In other words,
flow labels do not currently provide enough entropy to be useful for
flow hash generation in most instances.

Everyone understands that flow labels would help this problem.  This
draft is about what happens when the flow label is zero, which is the
case more often than not.

Nick