Re: [Snac] M/O Bit reflection behavior of draft-hui-stub-router-ra-flag-02

[Ted Lemon <[e-mail]>]

We've tried to update the documentation on the M&O bits before in the IETF.
It's failed because we can't get consensus.

Anyway, you're making a bunch of assertions here about what we have to do,
but not backing them with anything but your gut feeling based on
20-year-old experiences. I don't think this is helpful. I'm not trying to
minimize the importance of getting this right, and I appreciate your wish
to make sure that we do. But it's not clear to me that you are actually
talking about a real problem we need to solve. There was a lot of expertise
on this in the room when we discussed it, and the general consensus is that
the stuff you're describing is old news, and we don't need to worry about
it anymore.

It is true that the behavior of hosts is not consistent, because there is
no standard that tells them how to behave. But it is not true that there is
a problem, as far as we are able to tell. If you have data that suggests
otherwise, please share it. But please do not demand that we do very
difficult work to solve a problem that you haven't documented.

Also, on a more practical note, making changes to host behavior and the
treatment of M&O bits is very much not in charter for SNAC... :)

On Wed, Apr 17, 2024 at 3:18 PM Erik Auerswald <[e-mail]>
wrote:

> Hi Ted,
>
> On Wed, Apr 17, 2024 at 11:25:42AM -0400, Ted Lemon wrote:
> >
> > The behavior of the M and O bits isn’t defined anywhere.  Modern
> > hosts have had to adapt to this.  During the discussions we had in
> > Brisbane the consensus was that they do now handle inconsistent M&O
> > bits correctly.
>
> If the handling is not defined, no handling is incorrect.  But SNAC could
> describe how exactly hosts need to handle it to be compatible with SNAC.
> This would at least allow to troubleshoot the breakage.
>
> Alternatively, SNAC could refrain from sending RAs onto a managed link
> to prevent incompatibilities leading to problems.
>
> Alternatively, SNAC could make an honest effort to adapt to managed links,
> even if this does not work in all possible cases, and document the known
> problems in a section on operational considerations.
>
> Br,
> Erik
>