[146730] in North American Network Operators' Group
Re: Dynamic (changing) IPv6 prefix delegation
daemon@ATHENA.MIT.EDU (Owen DeLong)
Mon Nov 21 15:32:03 2011
From: Owen DeLong <owen@delong.com>
In-Reply-To: <4ECA6C97.6030208@dds.nl>
Date: Mon, 21 Nov 2011 12:27:55 -0800
To: Seth Mos <seth.mos@dds.nl>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Nov 21, 2011, at 7:21 AM, Seth Mos wrote:
> Hello List,
>=20
> As a pfSense developer I recently ran into a test system that =
(actually)
> gets a IPv6 prefix from it's ISP. (Hurrah).
>=20
> What is bewildering to me is that each time the system establishes a =
new
> PPPoE session to the ISP they assign a different IPv6 prefix via
> delegation together with a differing IPv4 address for the WAN.
>=20
> Is this going to be forward for other consumer ISPs in the world?
>=20
Unfortunately, there are some ISPs that believe this is the right thing =
to do.
Some go so far as to claim that scrambling customer prefixes is a =
mechanism
to help insure customer privacy.
> One of the thoughts that came to mind is T-Online in Germany that =
still
> disconnects it's (PPPoE) user base every 24 hours for a new random IP.
>=20
> Short of setting really short timers on the RA messages for the LAN I
> can see a multitude of complications for consumers in the long run.
>=20
Yep... It remains to be seen whether they will persist in this =
ill-conceived
behavior after the support calls start rolling in.
> People that configure their NAS, Media Player and Printer on their own
> network. And using ULA for either is not workable unless they somehow
> manage to grow DNS skill on the end user. Their NAS probably wants to
> download from the 'net and access videos from the NAS. The media =
player
> wants to be able to access youtube and the laptop needs to (reliably)
> find it's printer each time.
>=20
I suspect that mDNS/Rendezvous will become much more widespread in
the IPv6 household and will become the primary service discovery
mechanism. It actually works quite well and is relatively resilient to =
either
frequent renumbering or the ill-advised use of ULA.
> I really hope that ISPs will commit to assigning the same prefix to =
the
> same user on each successive connection.
>=20
It would be nice, but, I suspect there will always be some fraction of =
residential
ISPs determined not to do the right thing.
Look at the number that are refusing to make generous prefix allocations
to residential end users and limiting them to /56, /60, or even worse, =
/64.
Owen
