[arin-discuss] Trying to Understand IPV6

[Tim Howe]

On Mon, 13 Sep 2010 19:32:33 +0100
<michael.dillon at bt.com> wrote:

> > If I assigned a customer say an IPV4 /21 in IPV6 this would translate
> > into a /56? If I'm not mistaken a /56 would translate into something
> > like 65,000 host addresses? That just seems like a lot of hosts to me,
> 
> 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.  Not because you fear wasting
address space.  Currently, most folks will have a single IP (half of the
connecting range to their provider) and their LAN in RFC1918 space using
that address for NAT.  The IPv6 equiv to that would be a /64 connecting
range and another /64 range to use for their LAN.  This has been my plan
as most of these customers don't know (and don't wish to know) how to
subnet v4, so I am sure handing them a /48 and expecting them to use it
correctly is out of the question and unnecessary.  This seems to be what
HE is doing for tunnel accounts.

	Anyone wanting/needing multiple networks (or who even thinks they
might, and knows what a /48 is) can and should have a /48, no problem.

	I am just a small provider with mostly small business accounts
and colo, so maybe my situation isn't typical...

/64 per network
/48 per customer with more than one network (so they can have /64 per network)

	Is this flawed or no longer the prevailing way of thinking?

--
Tim Howe