Re: Definitive Guide to IPv6 adoption

[Owen DeLong <owen () delong com>]

On Oct 18, 2010, at 11:18 AM, Jon Lewis wrote:

> On Mon, 18 Oct 2010, Owen DeLong wrote:
>
> > The customers should get /48s. The /56 guideline is merely that and only for the smallest of sites. It's also 
> > subsequently turned out to be bad advice.
>
> Can you elaborate on why /56 is "bad advice" and if you're saying it only for this case or if you're saying 
> assignment of /56 to any customers is a bad idea?  Dealing with a data center where customer machines typically get 
> by today with a /29 of IPv4, is a /56 really not enough for their forseeable future?
I think it's generally a bad idea. /48 is the design architecture for IPv6. It allows for significant innovation
in the SOHO arena that we haven't accounted for in some of our current thinking.

In a datacenter environment, you might want to actually assign /64s to needed subnets, but, in a
situation where you are serving remote end-sites, a /48 per end-site is, IMHO, the minimum
size that should be issued.

> I realize our /32 could support more customers than we're likely to fit in the data center at /48 per customer, but 
> is that enough of a reason to assign 65k /64 subnets to each customer machine?
Datacenter is a whole different ball of wax. Nothing wrong with giving your customers /48s, 
but, the right size in a datacenter may well depend on a lot of things about your business
model, the nature of your customers, etc.

Certainly I would not deny a /48 to any customer that requested one.

Owen