Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)"

Brian E Carpenter <> Thu, 21 May 2020 21:32 UTC

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Subject: Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)"
To: "Ketan Talaulikar (ketant)" <>, Bob Hinden <>, IPv6 List <>
References: <> <>
From: Brian E Carpenter <>
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Date: Fri, 22 May 2020 09:32:38 +1200
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On 22-May-20 00:28, Ketan Talaulikar (ketant) wrote:
> **  Is there a charter milestone that explicitly calls for such a document?   ** *** 
> KT> No.

That is not an exclusionary argument. If it *was* a milestone, that would be supportive. But the absence of a milestone is like any other absence of evidence.
> **  Is the topic of the I-D within scope for the working group?   ** ***  
> KT> No. This is 6man WG; not anymore IPNG or IPV6. The WG charter clearly says “It is not chartered to develop major changes or additions to the IPv6 specifications.” 

That's a judgment call. IMHO a new routing header type is not "major". It's maintenance.
> KT> A new Source Routing technology (as claimed by the authors) is in the domain of expertise of the Routing Area (as the name suggests). 

Nobody can deny that, but a new RH type is in 6MAN's competence, as proved by the SRH case. I said the other day that advice from the Routing ADs is needed, and that remains true. But again, this is not an exclusionary argument.

> KT> Contrary to the claims by the authors, I would assert that this work simply brings a new IPv6 data_-_plane proposal for the Spring WG’s Segment Routing solution. 

Again, that's why this WG needs advice from the Routing ADs. But if it builds on SPRING work, so what? We build on each other's work constantly in the IETF, and that's a good thing. SPRING has no monopoly, and SRH has no monopoly.
> **  Is the purpose of the draft sufficiently clear?   ** ***
> KT> The purpose is not clear since the new IPv6 Source Routing solution claimed by the authors is not documented in the draft in terms of its applicability, use-cases and requirements. The header format and simplistic forwarding rules documented do not describe the architectural concepts of what a SID is, it’s semantics, “forwarding methods”, “method specific parameters”, etc. 

That's been discussed already with some new text proposed. But of course after the draft is adopted, we (the WG) own the the draft and can extend it as needed.

> KT> As observed in the WG discussion, members seem to be guessing or speculating on what would be a good size for the SIDs and how they would be used/deployed. This is clear proof that the solution is not described clearly.

That's of no importance at the adoption stage. The WG can improve the draft as needed. 
> **  Does the document provide an acceptable platform for continued effort by the working group?   ** ***

6MAN's job is limited to specifying the routing header. After that, it's up to the Routing Area to do the rest.

Your remaining questions are all irrelevant at the adoption stage. We are nowhere near talking about WG last call or submission to the IESG.

    Brian Carpenter