Re: [Idr] Éric Vyncke's No Objection on draft-ietf-idr-bgpls-srv6-ext-12: (with COMMENT)

[John Scudder <[e-mail]>]

Hi Éric,

> On Dec 15, 2022, at 6:38 AM, Eric Vyncke (evyncke) <evyncke=[e-mail]> wrote:
> 
> Thanks for educating me on this topic. The rationale makes sense but is not that apparent in the I-D, should the value be considered as opaque in BGP-LS ? I.e., not bearing any semantic for the BGP-LS component (but only to its users ?like a TCP/UDP payload ?)

I think that is the right way to think of it. Perhaps an explicit statement to that effect would be helpful (maybe it even exists already in 7752, for all I know, I haven’t checked). It isn’t clear to me that this draft is the right place to make the statement, although one can argue it's like the saying about the best time to plant a tree. Some of the language I proposed in my DISCUSS more-than-hints at this, but you’re right it could be even more explicit.

> There is still the question about IS-IS & OSPFv3 having the same set of flags *right now*. Would a divergence be allowed ? (broader scope question than this I-D)

I asked the LSR WG and authors of the IS-IS and OSPFv3 drafts about this yesterday, and the answer from Peter was an unequivocal “yes”:

> On Dec 15, 2022, at 6:29 AM, Peter Psenak <[e-mail]> wrote:
…
> On 14/12/2022 22:59, John Scudder wrote:
...
>> (This also leads me to wonder why we even put this registry, that’s shared by two (three?) protocols, under the IS-IS TLV Codepoints registry instead of under Interior Gateway Protocol (IGP) Parameters, but given the publication stage we’re at it may not be worth trying to change that.)
> 
> no, the flags are kept independent in each protocol.

(https://mailarchive.ietf.org/arch/msg/lsr/uIwdwIVns1SB4XClRbtdIN21pUk/)

Obviously, this makes it quite important to be clear in the BGP-LS spec about the points under discussion.

Thanks,

—John