Re: [spring] Question about SRv6 Insert function

Fernando Gont <> Tue, 03 September 2019 11:26 UTC

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To: Suresh Krishnan <>
Cc: Ron Bonica <>, li zhenqiang <>, draft-voyer-6man-extension-header-insertion <>, draft-ietf-spring-srv6-network-programming <>, "" <>, "" <>
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Date: Tue, 3 Sep 2019 14:17:41 +0300
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Subject: Re: [spring] Question about SRv6 Insert function
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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.

Put another way: what'd be the rationale for having a draft-ietf and
have the corresponding wg ship the document with something that clearly
goes against IETF consensus, and that the relevant AD has declared that
wouldn't let pass?

Fernando Gont
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