RE: Private use of non-RFC1918 IP space (IPv6-MW)

["TJ" <trejrco () gmail com>]

> > On Mon, Feb 2, 2009 at 9:35 PM, Patrick W. Gilmore
> > <patrick () ianai net>wrote:
> >
> > > Except the RIRs won't give you another /48 when you have only used
> > > one trillion IP addresses.
> >
> > Of course they will!  A /48 is only the equivalent of 65536 "networks"
> > (each network being a /64).  Presuming that ISPs allocate /64 networks
> > to each connected subscriber, then a /48 is only 65k subscribers, or
> > say around a maximum of 200k IP addresses in use at any one time
> > (presuming no NAT and an average of 3-4 IP-based devices per
> > subscriber)
> >
> > IPv4-style utilization ratios do make some sense under IPv6, but not
> > at the address level - only at the network level.
>
> First, it was (mostly) a joke.
>
> Second, where did you get 4 users per /64?  Are you planning to hand each
> cable modem a /64?


No, we should hand each home a /56 (or perhaps a /48, for the purists out
there) - allowing for multiple segments (aka subnet, aka links, etc.).  Note
- the actual number of hosts is irrelevant; the 64 bits on the host side of
the address are not meant to encourage 18BB hosts/segment.

Oh, and utilization should be based on /56s anyway.


/TJ