[arin-discuss] IPv6 End User Assignments

[Lee Howard]

----- Original Message ----
> From: Joe Maimon <jmaimon at chl.com>
> Cc: arin-discuss at arin.net
> Sent: Thursday, May 7, 2009 9:56:04 AM
> Subject: Re: [arin-discuss] IPv6 End User Assignments
> 
> 
> 
> michael.dillon at bt.com wrote:
> 
> > You have a warped sense of size and waste. A /21 is hardly
> > massive. With IPv4 I have received several /16 allocations
> > from ARIN, and in IPv6, a /21 or /16 represents the same
> > proportion of the total address space. 
> > In the IPv4 world
> > an ISP with a /21 is a small ISP in a single town. Waste
> > is simply not an issue with IPv6.
> 
> This seems contradictory.
> 
> > It is not a waste of space. Very large ISPs in Europe and
> > Asia already do assign /48s to each customer. ARIN policy
> > allows it in North America as well.
> > 
> 
> Only large ISP's can afford to do so with impunity. A /32 is not
> sufficient for a default allocation of /48 per customer. That makes it
> effectively only 16 times larger than an ipv4 /20, which suggests
> additional prefixes or renumbering pain.

I don't understand.  Show that you've used 36.9% of your /56s, and
document your two-year requirements, and you get another (adjacent) 
/32 (or whatever).  How is it different for large and small ISPs?

Note that NRPM says:

The exact size of the assignment is a local decision for the
LIR or ISP to make, using a minimum value of a /64 (when only one
subnet is anticipated for the end site) up to the normal maximum of
/48, except in cases of extra large end sites where a larger
assignment can be justified.
The following guidelines may be useful (but they are only
guidelines):
	* /64 when it is known that one and only one subnet is
needed
	* /56 for small sites, those expected to need only a few subnets
over the next 5 years.
	* /48 for larger sites
Lee