Am Dienstag, 21. Februar 2017, 18:27:39 schrieb Job Snijders:
> On Tue, Feb 21, 2017 at 09:49:32AM +0900, Lorenzo Colitti wrote:
> > On Tue, Feb 21, 2017 at 8:57 AM, Job Snijders <job@xxxxxxx> wrote:
> > > ps. The "Write a draft" argument is weak at best, since we are
> > > already are discussing a draft (called
> > > 'draft-ietf-6man-rfc4291bis-07.txt'), which is in IETF Last call,
> > > which means it is in a place to discuss the contents of that draft.
> > > No reason to kick the can down the road.
> >
> > I'm sorry, but that's really how it is. The text you dislike has been
> > the standard for almost 20 years, and is it inappropriate to change it
> > in the context of reclassifying this document from draft standard to
> > Internet standard.
>
> Or, perhaps it is inappropiate for the -bis document to target "Internet
> Standard" classification at this moment? ¯\_(?)_/¯
>
> Especially when solidifying recommendations in an architecture Internet
> Standard-to-be, the utmost care should be taken to verify whether the
> paper reality (RFCs) and operational reality (what people do, for
> $reasons) are aligned.
>
> In those years sufficient data has been collected to conclude that /64
> is not the "be all and end all". The current paragraph does not account
> for staticly configured environments in which SLAAC plays no role.
>
> Perhaps the following suggestion bridges the gap.
>
> -------
>
> OLD:
> IPv6 unicast routing is based on prefixes of any valid length up to
> 128 [BCP198]. For example, [RFC6164] standardises 127 bit prefixes
> on inter-router point-to-point links. However, the Interface ID of
> all unicast addresses, except those that start with the binary value
> 000, is required to be 64 bits long. The rationale for the 64 bit
> boundary in IPv6 addresses can be found in [RFC7421]
>
> NEW:
> IPv6 unicast routing is based on prefixes of any valid length up to
> 128 [BCP198]. When using [SLAAC], [ILNP], or [NPT66] the Interface ID
> of unicast addresses is required to be 64 bits long. In other use
> cases different prefix sizes may be required. For example [RFC6164]
> standardises 127 bit prefixes on inter-router point-to-point links.
> For most use cases, prefix lengths of 64 bits is RECOMMENDED, unless
> there are operational reasons not to do so.
Satisfies my desired outcome of the text, but I would like to modify it:
IPv6 unicast routing is based on prefixes of any valid length up to
128 [BCP198]. When using [SLAAC], [ILNP], or [NPT66] the Interface ID
of unicast addresses is required to be 64 bits long. An exception is for
example [RFC6164] which standardises 127 bit prefixes on point-to-point
links. The RECOMMENDED prefix length is 64 bit, but prefix lengths up to
128 bit can be possible on explicit configuration.
> OLD:
> As noted in Section 2.4, all unicast addresses, except those that
> with the binary value 000, Interface IDs are required to be 64 bits
> long.
>
> NEW:
> *delete, its superfluous*
Ok for me.