[109294] in North American Network Operators' Group
Re: NAT66 and the subscriber prefix length
daemon@ATHENA.MIT.EDU (Mikael Abrahamsson)
Fri Nov 14 14:29:08 2008
Date: Fri, 14 Nov 2008 20:28:47 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: nanog@nanog.org
In-Reply-To: <C0F2465B4F386241A58321C884AC7ECC0961B7FB@E03MVZ2-UKDY.domain1.systemhost.net>
Errors-To: nanog-bounces@nanog.org
On Fri, 14 Nov 2008, michael.dillon@bt.com wrote:
> Not long ago, ARIN changed the IPv6 policy so that
> residential subscribers could be issued with a /56
> instead of the normal /48 assignment. This was done
> so that ISPs with large numbers of subscriber sites
> would not exhaust their /32 (or larger) allocations
> too soon. Since these ISPs are allowed to assign
> a /56 to residential subscriber sites, their initial
> IPv6 allocation will last a lot longer and they won't
> have to apply for an additional allocation while
> everyone is getting up to speed with an IPv6 Internet.
We returned our /32 for a /25 (with /22 being reserved) and current plan
is to hand out /48s to everybody (unless they need even more space, then
they'll have to apply).
So, doing /56 to end users just because you happen to have a /32 right now
sounds like a bad plan, it doesn't take that many hours to get a larger
space if you can justify it (which wasn't that hard for us).
We received our /32 (as a /35 I think) back in 2000 or so, policy has
changed since then, with RIPE it's not that hard to get a much larger
space with a long term growth plan. My hope is that we'll make do with
this /22 space for at least 5-10 years (67 million customer /48s is quite
a lot), unless something really big happens, and then we'll just have to
get an even larger space.
So message should be that /48 to end users is the way to go, and this
should suit residential and SME market without any additional
administrative overhead depending on customer size.
--
Mikael Abrahamsson email: swmike@swm.pp.se
