Re: default-iids ready for WGLC? (Re: I-D Action: draft-ietf-6man-default-iids-10.txt)

[Lorenzo Colitti <[e-mail]>]

On Wed, Feb 17, 2016 at 8:09 PM, Fernando Gont <[e-mail]>
wrote:

> This rev addresses the feedback received on-list, mostly y Alex, Brian,
> and Ray.
>
> I personally think that this one should be ready for WGLC.
>

I have various objections to this document.

First: I don't see why the document require that the link layers MUST
provide stable identifiers. What if a link layer or a host does not want a
stable identifier? What about privacy threats?

I do not support the recommendation to use RFC7217 because doing so creates
a false sense of security. RFC 7217 and similar schemes provide protection
against some threats but not others. Randomizing the link-layer provides
much better protection, and is what other parts of the IETF are moving
towards - see for example draft-ietf-dhc-anonymity-profile, which pretty
much takes MAC address randomization as a given.

I-D.ietf-dhc-stable-privacy-addresses is in state dead and should be
removed.

In various places, the document talks about "the interface identifier".
This does not match reality because most IPv6 hosts have more than one IPv6
address formed using more than one IID.

I don't see how it's useful or constructive to suddenly declare billions of
implementations no longer compliant with specs that have been current for
nearly 20 years (e.g., RFC2464 is from 1998).

Instead of a sweeping update to lots of IPv6-over-foo documents, I'd much
rather see a best current practice that suggests that hosts do something
sane to address this sort of threat. "Something sane" should probably be
MAC address randomization, but could also be RFC7217+RFC4941, etc.

Regards,
Lorenzo