[101202] in North American Network Operators' Group
Re: v6 subnet size for DSL & leased line customers
daemon@ATHENA.MIT.EDU (Christopher Morrow)
Sat Dec 22 15:54:52 2007
Date: Sat, 22 Dec 2007 12:53:52 -0800
From: "Christopher Morrow" <morrowc.lists@gmail.com>
To: "Ross Vandegrift" <ross@kallisti.us>
Cc: "Deepak Jain" <deepak@ai.net>, "Joe Greco" <jgreco@ns.sol.net>,
nanog@merit.edu
In-Reply-To: <20071222202317.GB3844@kallisti.us>
Errors-To: owner-nanog@merit.edu
On Dec 22, 2007 12:23 PM, Ross Vandegrift <ross@kallisti.us> wrote:
>
> On Fri, Dec 21, 2007 at 01:33:15PM -0500, Deepak Jain wrote:
> > For example... Within one's own network (or subnet if you will) we can
> > absorb all the concepts of V4 today and have lots of space available.
> > For example... for the DMZ of a business... Why not give them 6 bits
> > (/122?) are we anticipating topology differences UPSTREAM from the
> > customers that can take advantage of subnet differences between /64 and
> > /56 ?
>
> I am confused on this point as well. IPv6 documents seem to assume
> that because auto-discovery on a LAN uses a /64, you always have to
> use a /64 global-scope subnet. I don't see any technical issues that
> require this though. ICMPv6 is capable of passing info on prefixes of
> any length - prefix length is a plain old 8bit field.
>
Uhm, so sure the spec might be able to do something different than /64
but most equipment I've used only does auto-conf if the prefix is a
/64 :( Somewhere along the path to ipng we got reverted to classful
addressing again :(
-Chris
