Re: IPv6 Ignorance

[Mark Blackman <mark () exonetric com>]

On 17 Sep 2012, at 15:55, Adrian Bool <aid () logic org uk> wrote:

> Hi,
>
> On 17 Sep 2012, at 15:02, Nick Hilliard <nick () foobar org> wrote:
> > On 17/09/2012 14:37, Adrian Bool wrote:
> > > It seems a tad unfair that the bottom 80 bits are squandered away with a
> > > utilisation rate of something closely approximating  zero
> >
> > You are thinking in ipv4 mode. In ipv6 mode, the consideration is not how
>
> > many hosts you have, but how many subnets you are dealing with.  Instead of
> > thinking of 128 bits of addressing space, we talk about 64 bits of subnet
> > space.  So your statement comes down to: "it seems a tad unfair that the
> > bottom 16 bits are squandered away".  This is a more difficult argument to
> > make.
>
> I don't really agree with the "IPv6 think" concept - but let's put that aside for now...
>
> The default allocation size from an RIR* to an LIR is a /32.  For an LIR providing /48 site allocations to their 
> customers, they therefore have 16-bits of address space available to them to address their customers.
>
> So, even in "IPv6 think", homes that typically have one subnet have an equal number of bits to address their single 
> subnet as an LIR has to address all of their customers.
>
> It seems illogical to me that we've got an 128-bit address space, featuring numbers far larger than any human can 
> comprehend, yet the default allocation to an LIR allows them to address such a feeble number as 65,536 customers - a 
> number far smaller than the number of customers for medium to large ISPs.
>
> The default LIR allocation should be a several orders of magnitude greater than the typical customer base  - not a 
> smaller default allocation.

Amen, brother! I was doing that particular computation about six months ago when we had
our first request and arrived at the same conclusion. I've concluded that /48 for businesses
and /56 for residential sites is the more reasonable approach until we start getting /24 IPv6
allocations for LIRs and I think many others have concluded the same.

- Mark