[ppml] IP-v6 Needs (RE: a modified proposal 2005-8)

[Michael.Dillon at btradianz.com]

> > This is the reason for giving EVERY end-site a /48. No matter
> > which network you connect to, you can get a /48 for your connection
> > and maintain the same internal subnet topology. The same issue 
> > arises with shipping containers, buses, travelling salesmen,
> > freight companies, and others.
> 
> If the space assigned to an end site is based upon what they need
> and their needs don't change while switching providers, then there
> should be no problem getting the same size prefix from each provider.
> Why does it have to be a /48?

First of all, it is not based on their needs in the
same way that IPv4 addressing is based on needs. Needs
based thinking is scarcity based thinking, and while it
is very appropriate for IPv4, it is not at all appropriate
for IPv6.

If providers were constantly allocating and reallocating
variable sized blocks then it would be a planning and
tracking nightmare. In a world where all customer allocations
are /48, it becomes much easier to plan and track. A certain
address block can be used by a shipping container today,
an airplane tomorrow, and the mayor's election campaign
office, the day after that. One size fits all.

This is related to the thinking behind flat-rate Internet
pricing versus usage-based schemes like 1980's long distance
phone calls. The flat-rate schemes seem to be unfair in 
economic terms at first glance. But when you factor in the
overall reduced rates caused by greatly reduced accounting
overhead, along with the ease of planning outgoing bills from
the customer side, flat-rate turns out to be economically
beneficial all-round.

We cannot afford to force the IPv6 networking world into
the mental strait-jackets of the IPv4 Internet any more
than we could afford to force the IPv4 Internet into the
mental strait-jackets of the telephony world. IPv6 really
is different and it is not just that which we currently
know as "the Internet".

--Michael Dillon