Re: [Wg-ipv6-guide] RE: Wg-ipv6-guide digest, Vol 1 #10 - 1 msg

[Anne Lord <anne@apnic.net>]

hi,

> > ----------8<----------8=----------8<----------8=----------8<----------
> > 5.3. LIR-to-ISP allocation
> > 
> > There is no specific policy for an organization (LIR) to allocate
> > address space to subordinate ISPs. Each LIR organization may develop
> > its own policy for subordinate ISPs to encourage optimum utilization
> > of the total address block allocated to the LIR.
> > 
> > However, all /48 assignments to end sites are required to be
> > registered either by the LIR or its subordinate ISPs in such a way
> > that the RIR/NIR can properly evaluate the HD-Ratio when a subsequent
> > allocation becomes necessary.
> > ----------8<----------8=----------8<----------8=----------8<----------
> > 
> > My interpretation is same as yours (bellow).
> > 
> >  | -------------------------------------------------------------------------
> >  |  - If a sub-allocation is made to a down stream ISP, but not
> >  |    assignments are registered in the database, it will not considered
> >  |    utilized
> >  |    e.g.) /40 sub-allocation is made to a downstream ISP. 2*/48 is
> >  |          assigned from this block. In this case, 2*/48 is considered
> >  |          as utilized, not /40(256*/48).
> >  | -------------------------------------------------------------------------
> > 
> OK, thanks for your comment.
> Any opinions from the others?

The interpretation is correct. The basis for measuring utilisation
is the HD ratio value for the prefix. Therefore indeed one /40 
allocation may be partially used, and other almost completely full. What
matters is meeting the HD ratio value in terms of the number of
/48 assignments.  The distribution of those /48's is not important.

> >  | In anycase, whichever the interpretation is, I think it is worth
> >  | noting it in the document since it is quite confusing.
> > 
> > Agreed. 
> > 
> > I think it's helpful to describe clearly as 'this is [same
> > as/different from IPv4]'.
> > 
> > And if Okutani-san's interpretation is correct, it's better to add the
> > comment that 'So, LIRs should carefully consider and justify the
> > sub-allocation size'.  I'm not sure this kind of notification should
> > be written or not in guidelines document.
> I think it's a good idea to include it as an advice.
>  
> > 
> > This is Okutani-san's previous mail:
> > 
> >  | Also, this should probably go into the initial allocation section, but
> >  | let me comment on one point which came up to my mind.
> >  | 
> >  | It may be worth noting that at the time of the initial allocation
> >  | request, sub-allocations to downstream ISPs are taken into account as
> >  | "to be assigned /48".
> > 
> > Does this mean at the initial allocation request, ISPs can take into
> > account the number of users in down stream ISPs?
> This is just my personal interpretation, but this is how I understand
> the policy.
> 
> At the time of the initial allocation request, LIRs do not need to be
> concious if the number of assignments planned through its downstream
> ISP. They simply need to worry about the size of sub-allocations to
> the downtream.
> 
> Therefore, when an LIR states a plan in its allocation request that
> they will sub-allocate /40 to a downstream ISP, then it is considered
> as an equivalent of the LIR having a plan to assign 256*/48 to
> sites/POPs.
> 
> The RIR/NIR will not check the details of the assignment plan of the
> downstream ISP at the time of the initial allocation request.
> 
> However, if an LIR sub-allocates an unrealistic size to its
> downstream, they will not be able to meet the utilization rate at the
> subsequent allocation since it will be judged based on the number of
> /48 registrations, not the size of sub-allocations to the downstream
> ISP.

yes this is correct.

> Initial allocation request:
>  /44 sub-allocation
>  -->can be considered as the equivalent of 16 * /48
>  -->no need to provide the details of /44 sub-allocation
> 
> Subsequent allocation request:
>  /44 sub-allocation, but no /48 assignments registered in registry database
>  --> not considered as utilized(0 * /48 assignment)
> 
> I hope I succeeded in clarifying the difference, but please let me
> know if further explanation is needed.

Yes this makes sense to me. The main note I think is that which was
mentioned above. That organisations should try to make sensible sub-
allocations so that they can meet the HD utilisation measure. 

Anne
--

> Feedbacks are also welcome!
> 
> 
> Izumi
> JPNIC
> 
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