[arin-discuss] IPv6 End User Assignments

[michael.dillon at bt.com]

> As architects in the planning phase of a v6 roll-out we get 
> to plan for company needs, customer needs, aggregation, 
> reachability, scalability, etc etc etc. One of the aspects we 
> should all evaluate is wasting space.  

NO!

First of all, don't call yourself an architect if you know
nothing about the technology. Architects start by learning
how things work, then and only then, do they design and plan.
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.

> When I rolled out v6 to my customers, I made the company 
> policy decision to assign /64s to customers by default and 
> /48s to those who requested more than one subnet.  This made 
> it rather easy to have 2 pools of aggregatable regional space 
> for customer assignments.

Some of use prefer one pool which can be achieved by giving
everyone a /48. On the business side of things, when competitors
appear offering a /48, this means that you would already
be at parity instead of losing customers steadily because of
your stinginess. If I were in your market, I would portray
this as evidence of your technical incompetence to encourage
your customers to jump ship. (Note that I don't run an ISP
so there is no danger of me personally being in your market).

> It is highly unlikely that very large ISPs will be assigning 
> 48s to each customer as it would be a waste of space.

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.

> I am involved in many v6 implementations and none of them 
> assign 48s by default.

No doubt due to your influence. But sooner or later these 
people will educate themselves about IPv6 and will be unhappy
with the way that you forced them down an unsustainable path.

--Michael Dillon