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

stefano previdi <> Tue, 26 May 2020 18:03 UTC

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Subject: Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)"
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From: stefano previdi <>
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Date: Tue, 26 May 2020 20:02:50 +0200
Cc: Bob Hinden <>, IPv6 List <>
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To: Ron Bonica <>
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Hi Ron,

> On May 26, 2020, at 6:25 PM, Ron Bonica <> wrote:
> Stephano,

/ph/f   ;-)

> The drafts that you mention below can be categorized as follows:
> - those that are entirely independent of the SRv6 architecture
> - those thar are entirely dependent upon the SRv6 architecture

I don’t disagree but, in my humble view and opinion, the 4 mentioned drafts aim to the same objective which is related to the size of the routing header (whatever flavor) containing the segment list.

I really wish that 6man will take time to review and process all these proposals before calling for adoption individual ones. Ideally, we shouldn’t standardize competing options or, at least, we should try to rationalize the spectrum of available solutions.

You argument about architectural linkage is very welcome to be discussed during this evaluation process (well, in fact it looks it’s already well discussed ;-)

Let’s keep the door open and let’s bring _all_ the options on the table before jumping to conclusions. An adoption today would give the message that one option is already the preferred one. This, I think, it’s not reflected in the state of the discussion.

For all these reasons I still don’t support the adoption of draft-bonica-6man-comp-rtg-hdr.


> The CRH falls into the first category because it does not rely upon instructions being encoded in the IPv6 destination address. It assumes RFC 4291 address semantics.
> All of the other drafts rely on some special interpretation of the IPv6 address. Either:
> - The IPv6 address includes an instruction that describes how subsequent routing headers are to be processed
> - The IPv6 address represents a path instead of an interface

> For that reason, it makes sense to:
> - progress the CRH draft, independently of SRv6
> - let the SPRING WG evaluate the other drafts and send one of them to 6man.
>                                                                       Ron
> Juniper Business Use Only
> -----Original Message-----
> From: ipv6 <> On Behalf Of stefano previdi
> Sent: Tuesday, May 26, 2020 9:40 AM
> To: Bob Hinden <>om>; IPv6 List <>
> Subject: Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)"
> [External Email. Be cautious of content]
> Hi,
> As author of the original SRH proposal, I follow with quite some interest the discussion around the need of compression of the segment list. At this stage I see at least 4 proposals, each of which brings some valid and interesting arguments:
> . draft-bonica-6man-comp-rtg-hdr
> . draft-decraene-spring-srv6-vlsid
> . draft-lc-6man-generalized-srh
> . draft-filsfils-spring-net-pgm-extension-srv6-usid
> . (maybe there are more...)
> Also, it looks to me that the ongoing discussion is focused only on one of the above. Are we going to re-spin the same debate for each of these or do we want the WG to conduct an analysis on all of them prior to select one (or maybe two) that would be candidate for adoption ? Certainly, I’d prefer the latter.
> So, at this stage I don't support the adoption of draft-bonica-6man-comp-rtg-hdr and would prefer to see the WG to start an exhaustive analysis on all of the proposals.
> Thanks.
> s.
>> On May 16, 2020, at 12:13 AM, Bob Hinden <> wrote:
>> This message starts a two-week 6MAN call on adopting:
>> Title:          The IPv6 Compact Routing Header (CRH)
>> Authors:        R. Bonica, Y. Kamite, T. Niwa, A. Alston, L. Jalil
>> File Name:      draft-bonica-6man-comp-rtg-hdr-21
>> Document date:  2020-05-14
>> as a working group item. Substantive comments regarding adopting this document should be directed to the mailing list.  Editorial suggestions can be sent to the authors.
>> Please note that this is an adoption call, it is not a w.g. last call for advancement, adoption means that it will become a w.g. draft.  As the working group document, the w.g. will decide how the document should change going forward.
>> This adoption call will end on 29 May 2020.
>> The chairs note there has been a lot of discussions on the list about this draft.   After discussing with our area directors, we think it is appropriate to start a working group adoption call.  The authors have been active in resolving issues raised on the list.
>> Could those who are willing to work on this document, either as contributors, authors or reviewers please notify the list.   That gives us an indication of the energy level in the working group
>> to work on this.
>> Regards,
>> Bob and Ole
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