[arin-discuss] Trying to Understand IPV6

[Tim Howe]

On Tue, 14 Sep 2010 12:13:14 +0100
<michael.dillon at bt.com> wrote:

> > > Anyone in this position should simply assign a /48 to every customer
> > site
> > > no matter how big or small. A one bedroom apartment gets a /48. A
> > manufacturing
> > > plant with 5 buildings including a 4-story office block, gets a /48.
> > > No exceptions.
> > 
> > 	This is slightly different than I have been led to think...  It
> > seems wise, when you know the customer has no intention of having
> > multiple networks, to provide a /64.  
> 
> That is not wise, it is foolish.

	...

> That is an IPv4 plan, not an IPv6 plan. IPv6 is not just IPv4
> with longer addresses, it has a very different idea of how 
> addressing is done, and it intentionally wastes space to make
> sure that networks can be expanded at several levels without 
> needing to change the addressing architecture. If you don't provide
> the slack, then you are breaking IPv6 and recreating the problems
> of IPv4.

> It is very typical. /48 to every customer, no exceptions.

	I am now convinced that this is the best policy for end user
sites...

> The flaw is in thinking that a customer has only one network. Most folks
> these days have two, one wired and one wireless. They may not be using
> both, but it is there in the gateway router and they could turn on the
> second network any day now.

	I think single colocated servers may be an exception.  Today we
simply supply a /30 to many of them and they use the one IP and our
router is their gateway.  I'm not sure these servers need more than a /64
connecting range.  Some colo customers have their own routers/firewalls
and a /48 is obvious for them, but is there reason to think these
one-server folks need more than a /64?

--
Tim Howe