Re: [spring] Network Programming - Penultimate Segment Popping

Fernando Gont <fernando@gont.com.ar> Thu, 05 December 2019 20:51 UTC

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To: "Darren Dukes (ddukes)" <ddukes@cisco.com>, Ron Bonica <rbonica=40juniper.net@dmarc.ietf.org>
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From: Fernando Gont <fernando@gont.com.ar>
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Message-ID: <adcc1d5c-854a-500a-818e-9bc6b742ff58@gont.com.ar>
Date: Thu, 5 Dec 2019 17:50:41 -0300
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Archived-At: <https://mailarchive.ietf.org/arch/msg/spring/obap8M8qVH8aFJ0bwzCZt4QTaBw>
Subject: Re: [spring] Network Programming - Penultimate Segment Popping
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On 5/12/19 13:50, Darren Dukes (ddukes) wrote:
> Hello Ron, I believe this is the fifth time you have raised this comment
> in 6man and/or spring.
> The comment has been addressed in earlier iterations. 
> 
> Let me recap.
> 
> With the PSP behavior, the SRH is only removed by the node identified in
> the destination address field of the IPv6 header.

The question if simple: If SRH is removed by the very node identified by
the destination address when SL !=0, then that's a middlebox mangling
with SRH, and not allowed by RFC8200.


  
> That destination address was placed in the SRH by the SR Source node,
> fully expecting the behavior.

Yes, SRv6 folks have expected insertion, too. However, we have an
internet standard that forbids that (including removal by middleboxes),
and hence that's not allowed -- unless you get consensus to update RFC8200.

Thanks,
-- 
Fernando Gont
e-mail: fernando@gont.com.ar || fgont@si6networks.com
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