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Re: draft-wang-6man-flow-label-reflection

Brian E Carpenter <brian.e.carpenter@gmail.com> Fri, 21 November 2014 01:50 UTC

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Date: Fri, 21 Nov 2014 14:50:23 +1300
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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To: Florent Fourcot <ietf@flo.fourcot.fr>
Subject: Re: draft-wang-6man-flow-label-reflection
References: <5465C0AC.10801@massar.ch> <54673BF1.3030806@flo.fourcot.fr>
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Florent,

Where I can I find an algorithm description (or the code) for
skb_get_hash ? I'm curious to know whether it meets the requirements
described in RFC 6437. The algorithm suggested in the appendix of that RFC
is lousy, as shown at https://www.cs.auckland.ac.nz/~brian/flowhashRep.pdf
FNV1a-32 is much better, for example.

Regards
   Brian

On 16/11/2014 00:41, Florent Fourcot wrote:
> Hello,
> 
>> but I have not found a hardware device yet that is actually
>> using it for that purpose,
> 
> You are aware of the ECMP problem, so you should know that the Linux
> kernel already use flow labels for that. And it is embedded in many
> hardwares.
> 
> Some links:
> 
>  * http://patchwork.ozlabs.org/patch/343108/
>  * http://permalink.gmane.org/gmane.linux.network/321696
> 
> Best regards,
>

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