Re: [v6ops] WGLC for draft-ietf-v6ops-rfc3849-update-01

[Rob Foehl <[e-mail]>]

On Fri, 2023-12-15 at 16:45 -0600, Nick Buraglio wrote:
> > Do we really want to more special address space / RFC1918-like space in IPv6?
> > If nothing else it has real operational cost. Everyone must update their edge filters.
> > 
> > While I’m skeptical that more documentation space is needed.
> > 

> One critical detail is that we need to ensure whatever it is that we end up with makes it into bogon filters and other BCPs for routing security. 
> 
> WGLC ends today, so any further support or non-support should be voiced ASAP. 

I wasn't going to wade into this, but with the original /20 somehow
ballooning into multiple /16s or a /12...

As a practical matter: meh.  It's a minor nuisance to have to update
prefix lists in all of the requisite places.

As a matter of principle: completely opposed.  While it may be a minor
nuisance, the number of changes required globally does add up, and I
don't recall seeing any attempts at a cost-benefit justifying that
effort.

Moreover, the plausible uses seem to fall into a few cases for which
practicable solutions exist:

- Documentation of a real network: use the real prefix(es).

- Documentation for a specialized audience, e.g. RIR justification: any
arbitrary placeholder will suffice.  They'll be fine.  There's even a
TBD::/20 right there in the draft...

- Documentation for educational purposes: again, any placeholder will
suffice, as many as deemed necessary.  ispA::/28, ispB::/24, ...

The recurring theme being *documentation*, which is of course the sole
stated purpose.  The space actually being configurable in any capacity
or usable for any other purpose is at odds with at least 3849 section 3
and the (somewhat self-contradictory) revised section 3 in the draft. 
Any such addresses would not, by definition, be documentation; any
proposals for same, cf. mentions of lab space, ought to stand on their
own merit.

More documentation space isn't necessary -- not from GUA space, anyway.

-Rob