Re: [spring] Question about SRv6 Insert function

Fernando Gont <> Thu, 05 September 2019 14:55 UTC

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To:, Fernando Gont <>
Cc: Ron Bonica <>, "" <>, "" <>, Suresh Krishnan <>, draft-voyer-6man-extension-header-insertion <>, draft-ietf-spring-srv6-network-programming <>, li zhenqiang <>
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Subject: Re: [spring] Question about SRv6 Insert function
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On 5/9/19 17:46, wrote:
> Fernando,
>> From: spring [] On Behalf Of Fernando Gont
>> Sent: Tuesday, September 3, 2019 1:18 PM
>> Hello, Suresh,
>> On 2/9/19 19:07, Suresh Krishnan wrote:
>> [....]
>>>>> So, we should probably explore the motivation for Option 2). If the
>>>>> motivation is not sufficient, we should probably standardize on Option 1.
>>>> My argument would be:
>>>> Folks would do whatever they please with 1). If somehow they feel the
>>>> need to do 2), they should *refrain from even suggesting it*, post an
>>>> internet draft that proposes to update RFC8200 to allow for the
>>>> insertion of EHs, wait for that to be adopted and published, and only
>>>> then suggest to do EH insertion.
>>> I have put down my thoughts on the future of header insertion work in a
>>> mail to the 6man list in May 2017. The mail can be found below
>> This seems e bit misleading. What I would expect is that before any work
>> is published on EH-insertion, the IPv6 standard is updated to allow for
>> EH insertion. (plese see bellow)
>>>> P.S.: Given the amount of discussion there has been on this topic in the
>>>> context of RFC8200, I'd like to hope that there's no draft-ietf document
>>>> suggesting EH-insertion or, if there is, the relevant ADs and chairs
>>>> make sure that's not the case anymore.
>>> Yes. If a draft violates RFC8200 and it hits the IESG for evaluation, I
>>> will certainly hold a DISCUSS position until the violations are fixed.
>> Since there have been plenty of attempts to do EH insertion or leave the
>> IPv6 standard ambiguous in this respect, and the IETF has had consensus
>> that EH insertion is not allowed, I think it would be bad, wastefull,
>> tricky, and even dangerous to let a document go through the whole
>> publication process, and just rely on the AD to keep the "DISCUSS"
>> button pressed.
> draft-ietf-spring-srv6-network-programming has a normative reference to [I-D.voyer-6man-extension-header-insertion]
> As such, from a process standpoint, it would not going to be published before [I-D.voyer-6man-extension-header-insertion] be itself published as RFC. And from its name, the latter is intended to be discussed and within control of the 6MAN WG. So I don't think that we can say that it "just rely on the AD to keep the "DISCUSS" button pressed."
> In my mind, this should also be a clear indication that the question of header insertion is (to be) within the control of the 6MAN WG. But you may have a different opinion.

Maybe my mental algorithm has a bug, but: what's the point of spring
working on a document that relies on something that 6man has so far

You spend energy on the document and then... just sit on the I-D to see
if 6man adopts voyer-6man-extension-header-insertion? Ship the document
to the IESG for them to review? -- I'm lost, sorry.

Fernando Gont
SI6 Networks
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