Re: [spring] Network Programming - Penultimate Segment Popping

Fernando Gont <fgont@si6networks.com> Sat, 07 December 2019 15:19 UTC

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To: "Darren Dukes (ddukes)" <ddukes@cisco.com>, Ron Bonica <rbonica@juniper.net>
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From: Fernando Gont <fgont@si6networks.com>
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Date: Sat, 7 Dec 2019 12:19:26 -0300
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Subject: Re: [spring] Network Programming - Penultimate Segment Popping
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On 7/12/19 12:10, Darren Dukes (ddukes) wrote:
> Ron, you say
>>>  RFC 8200 addresses extension header insertion and deletion
> identically, in the same sentence.
> 
> This sentence you refer to clearly permits PSP as defined in network
> programming:
>    Extension headers (except for the Hop-by-Hop Options header) are not
>    processed, inserted, or deleted by any node along a packet's delivery
>    path, until the packet reaches the node (or each of the set of nodes,
>    in the case of multicast) identified in the Destination Address field
>    of the IPv6 header.
> 
> Clearly we process the SRH at the node identified in the destination
> address field of the IPv6 header.
> With PSP we remove the SRH at the node identified in the destination
> address field of the IPv6 header.
> 
> I think it’s clear we can conclude this thread.

Can you tell me which address, other than the address of the final
destination, can be present in the DA of a pcket, in the context of RFC8200?

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
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