[101346] in North American Network Operators' Group
Re: v6 subnet size for DSL & leased line customers
daemon@ATHENA.MIT.EDU (Mark Smith)
Mon Dec 31 18:58:55 2007
Date: Tue, 1 Jan 2008 10:27:50 +1030
From: Mark Smith <nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org>
To: Joel Jaeggli <joelja@bogus.com>
Cc: Jeroen Massar <jeroen@unfix.org>, surfer@mauigateway.com, nanog@merit.edu
In-Reply-To: <47795CB1.1010900@bogus.com>
Errors-To: owner-nanog@merit.edu
On Mon, 31 Dec 2007 13:18:41 -0800
Joel Jaeggli <joelja@bogus.com> wrote:
>
> Mark Smith wrote:
>
> >
> > Another idea would be to give each non-/48 customer the
> > first /56 out of each /48. If you started out with a /30 or /31 RIR block , by
> > the time you run out of /48s, you can either start using up the
> > subsequent /56s out of the first /48, as it's likely that the first /56
> > customer out of the /48 would have needed the /48 by that time.
>
> As stated, that approach has really negative implications for the number
> of routes you carry in your IGP.
>
Well, for 120K+ customers, I doubt you're using an IGP for anything
much more than BGP loopbacks - and you'd have to be aggregating routes
at a higher layer in your routing hierarchy anyway, to cope with 120K
routes, regardless of what method you use to dole out /48s or /56s to
end-sites.
> > Alternatively you might have become more comfortable with giving each
> > customer a /48, and wouldn't require any of them to renumber - they'd
> > just have to shorten their prefix length.
> >
> > Regards,
> > Mark.
> >
>
--
"Sheep are slow and tasty, and therefore must remain constantly
alert."
- Bruce Schneier, "Beyond Fear"
