[121779] in North American Network Operators' Group
Re: Using /126 for IPv6 router links
daemon@ATHENA.MIT.EDU (Mark Smith)
Tue Jan 26 23:54:14 2010
Date: Wed, 27 Jan 2010 15:23:38 +1030
From: Mark Smith <nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org>
To: Tim Durack <tdurack@gmail.com>
In-Reply-To: <9e246b4d1001260813q1898ee9fq82d344d2fac99902@mail.gmail.com>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Tue, 26 Jan 2010 11:13:22 -0500
Tim Durack <tdurack@gmail.com> wrote:
> On Mon, Jan 25, 2010 at 11:06 PM, Mark Smith
> <nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org> wrote:
> > On Mon, 25 Jan 2010 15:15:55 -0500
> > "TJ" <trejrco@gmail.com> wrote:
>=20
> >> I didn't realize "human friendly" was even a nominal design considerat=
ion,
> >> especially as different humans have different tolerances for defining
> >> "friendly" =A0:)
> >>
> >
> > This from people who can probably do decimal to binary conversion
> > and back again for IPv4 subnetting in their head and are proud of
> > it. Surely IPv6 hex to binary and back again can be the new party
> > trick? :-)
>=20
> Maybe we can all do this stuff in our head, but I have found removing
> unnecessary thinking from the equation is useful for those "3am"
> moments.
>=20
> Given that I am assigning a /48 to a site anyway, and 65k /64s is
> "more than I will ever need", does it really matter if the
> site-specific numbering plan isn't ruthlessly efficient?
>=20
The general intent of the /48 allocation is that it is large enough for
nearly everybody, with nearly everybody including all but the largest
of organisations. IOW, it's meant to be "nearly one-size-fits-all", to
try to ensure almost everybody gets as much address space as they'll
ever need at the time of their first request. An addressing plan for
anything less than the largest organsation that doesn't fit within
a /48 or will exceed it fairly rapidly is probably too inefficent.
ps. Remember that I'm one of the ones advocating using /64s everywhere,
so what ever you do, don't use "ruthlessly efficient" to describe my
position - use that for the /126 or /127 crowd ;-)
Regards,
Mark.
