Re: [spring] We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping)

Brian E Carpenter <> Sat, 07 December 2019 02:48 UTC

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To: Fernando Gont <>, Andrew Alston <>, Ole Troan <>
Cc: Ron Bonica <>, SPRING WG <>, 6man <>, "" <>, rtg-ads <>, Bob Hinden <>
References: <> <> <> <> <>
From: Brian E Carpenter <>
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Date: Sat, 7 Dec 2019 15:47:53 +1300
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Subject: Re: [spring] We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping)
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Again, comment at the end...
On 07-Dec-19 14:37, Fernando Gont wrote:
> On 6/12/19 22:15, Brian E Carpenter wrote:
> [...]
>>> and if such a thing is required, an update to RFC8200 should be done.
>> Why does that follow? Alternatively, draft-ietf-spring-srv6-network-programming could acknowledge that it deviates from RFC8200.
> You can deviate from s "should", not from a "must". This is an outright
> violation of a spec, rather than a mere "deviation".
>> Whether that's acceptable would be a question for the IETF Last Call rather than any single WG.
> I would expect that a WG cannot ship a document that is violating an
> existing spec, where the wg shipping the document is not in a position
> of making decisions regarding the spec being violated.
> That would be like a waste of energy and time for all.
>> At the moment, the draft only mentions RFC8200 in a context that discusses neither insertion nor removal of extension headers, which is beside the point. Like draft-voyer, if it describes a violation of RFC8200, shouldn't that be explicit in the text?
>> There's a lot of jargon in draft-ietf-spring-srv6-network-programming. I can't tell from the jargon whether "insert" means "insert on the fly" and whether "Pop the SRH" means "delete on the fly". Should those terms be clarified before the draft advances?
> Well, if it's not clear to you, it would seem to me that the simple
> answer would be "yes".

But if "insert" refers to the encapsulating node at the SR domain ingress, it's no problem, and if "pop" simply means doing normal routing header processing, it's no problem. It simply isn't clear in the text, at least not clear to me.