[Re: http://tools.ietf.org/search/draft-hain-ipv6-ulac-01]

bmanning at vacation.karoshi.com bmanning at vacation.karoshi.com
Wed Apr 21 17:05:01 CDT 2010

On Thu, Apr 22, 2010 at 07:17:20AM +0930, Mark Smith wrote:
> On Wed, 21 Apr 2010 09:25:46 -0400
> Christopher Morrow <morrowc.lists at gmail.com> wrote:
> > On Wed, Apr 21, 2010 at 1:29 AM, Owen DeLong <owen at delong.com> wrote:
> > > While I think this is an improvement, unless the distribution of ULA-C is no cheaper
> > > and no easier to get than GUA, I still think there is reason to believe that it is likely
> > > ULA-C will become de facto GUA over the long term.
> > >
> > > As such, I still think the current draft is a bad idea absent appropriate protections in
> > > RIR policy.
> > 
> > I agree with owen, mostly... except I think we should just push RIR's
> > to make GUA accessible to folks that need ipv6 adress space,
> > regardless of connectiivty to thegreater 'internet' (for some
> > definition of that thing).
> > 
> > ULA of all types causes headaches on hosts, routers, etc. There is no
> > reason to go down that road, just use GUA (Globally Unique Addresses).
> > 
> So what happens when you change providers? How are you going to keep
> using globals that now aren't yours?
> I'm also curious about these headaches. What are they?

I'm so not creative enough to compose this whole missive in TLAs... perhaps some day.

Some bright blub got tired of typing out "Globally Unique Addresses) and so started
using the TLA/GUA.

Which eventually got me to thinking.  Technically, all IP addresses are globally unique.
There is only one of them. is a GUA.  There are however, two other
vectors which the community seems to want and we talk around them a whole bunch.
Perhaps we should explicitly make them part of the conversation.

) A GUA has a single authoritative chain of custody...  e.g. the community recognizes
        that only Bill Manning's Bait and Sushi shoppe (AS 66,666)  is authorized to
        inject routes for and sink traffic to
        The whole rPKI construct is built to support this idea.  Now some prefixes are
        defined to -NOT- have a single authoriative chain of custody, witness RFC 1918.
        And NAT makes matters "fuzzier" ... bringing scoping into the mix - but I'll
        stick by the postualte that this single authoritative chain of custody is
        a key point in understanding how folk think of IP stewardship ... and 
	(THIS IS IMPORTANT) ... there is this strong idea that a short custody chain
	is prefered over a long one.  

) A GUA is temporally bound**...  e.g. the community recognizes that for any given GUA, there
        is a temporal bounding on the chain of custody.  DHCP is a canonical example for
        end/leaf sites, where GUAs are leased out for (comparitavely) brief time periods.
        ISPs lease space to their clients for longer periods, and RIRs are (mostly) binding
        a chain of custody to annual cycles.  For some legacy space, the temporal binding
        is of -much- longer duration. 

so... I might argue that the IANA/RIR/LIR/Enterprise chain has the renumbering concern
that you raise, while a IPR/Enterprise chain is much shorter and has a smaller renumbering

and -IF- the permise and details of the draft are to be beleived, then a delegation
from that space is just as much assured of global uniqueness than space from an RIR.

** The Temporaly Unique Address/TUA !!!

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