/48 vs. /56 for customers, was XS4ALL Introduces native IPv6 for DSL customers

[Shane Kerr]

Daniel,

On Fri, 2010-08-27 at 09:49 +0200, Daniel Roesen wrote:
> On Fri, Aug 27, 2010 at 09:16:09AM +0200, Marco Hogewoning wrote:
> > Als a lot of folks out there once heard about the 48 and are still
> > sticking to it, even when the policy differs. Saves ourself a lot
> > of discussion and waving policy.
> 
> Unless you run out of /48s and have to go back to RIPE NCC to get more
> address space. And then you're judged on /56s, not /48s for efficiency.

Hm... that's a good point.

With at "normal" /32 allocation you can only give 65k customers a /48,
which is non-trivial but also almost certain to happen sooner or later.
So any ISP of size will run out of address space if they use /48, and
then will have to shift to /56 eventually.

Best to use /56 initially? Perhaps this should be a strong
recommendation somewhere?

--
Shane