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Re: [spring] PSP and a logical application of RFC8200

Fernando Gont <fgont@si6networks.com> Mon, 02 March 2020 20:46 UTC

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To: "Pablo Camarillo (pcamaril)" <pcamaril=40cisco.com@dmarc.ietf.org>, Brian E Carpenter <brian.e.carpenter@gmail.com>, "Darren Dukes (ddukes)" <ddukes=40cisco.com@dmarc.ietf.org>, 6man WG <ipv6@ietf.org>, SPRING WG List <spring@ietf.org>
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From: Fernando Gont <fgont@si6networks.com>
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Date: Mon, 02 Mar 2020 17:45:22 -0300
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Subject: Re: [spring] PSP and a logical application of RFC8200
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On 2/3/20 17:02, Pablo Camarillo (pcamaril) wrote:
> Brian,
> 
> The PSP pseudocode is presented as a modification to the End pseudocode starting at line S14 of such.
> Please go through the PSP pseudocode in conjunction with the End pseudocode (Section 4.1).
> You will see that the ingress state of the packet is (Segments Left == 1 and Destination Address == the PSP node's address).

You are also changing the semantics of routing headers: if you prcessed 
the RH when Segments Left == N, you don't get to decrement SegmentsLeft 
and process the routing header again.

So, again, you should be updating RFC8200, and probably even the 
segment-routing-header I-D.

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492

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