[125912] in North American Network Operators' Group
Re: [Re: http://tools.ietf.org/search/draft-hain-ipv6-ulac-01]
daemon@ATHENA.MIT.EDU (Owen DeLong)
Mon Apr 26 11:05:47 2010
From: Owen DeLong <owen@delong.com>
In-Reply-To: <4BD586BD.4060002@hoyle.me.uk>
Date: Mon, 26 Apr 2010 08:01:37 -0700
To: Tony Hoyle <tony@hoyle.me.uk>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Apr 26, 2010, at 5:27 AM, Tony Hoyle wrote:
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>=20
> On 26/04/2010 08:08, Mark Smith wrote:
>=20
>>=20
>>> How much do you understand about IPv6 addressing? Are you aware that
>>> IPv6 addresses have explicit preferred and valid lifetimes, and
>>> therefore they can change over time?
>=20
> Only via privacy extensions.. and I always switch them off as they're =
a
> pain in the neck. Even with those they don't change the prefix.
>=20
Uh, no... If you're using slack, IPv6 addresses have explicit preferred =
and valid
lifetimes for the PREFIX which can change over time at the decision of =
the
person running the device(s) issuing the RAs.
> My /48 is allocated to me.. In no sane world would that suddenly
> change, unless I did something major like change ISP, any more than my
> v4 address would suddenly change.
>=20
Agreed, mostly. If your provider issues your /48 to you via DHCP-PD, =
then,
it, too, has a desired and valid lifetime which is expected to be passed =
along
in your subordinate RAs, and, it means that if they reconfigure their =
DHCP
server, you are expected to abide by the change.
> You're trying to say ipv6 prefixes change randomly over time - just
> think of the implications if that could happen... even basic things =
like
> firewalling would become a nightmare.
>=20
Whether they do or not depends on your circumstance and the design
of upstream networks. They may or may not. Certainly it is desirable
from a customer perspective that they do not. It may be equally =
desirable
from a carrier perspective that they do. Personally, I hope carriers =
will
design their networks well enough that changing prefixes at random
times is not necessary and customers can get a better IPv6 experience.
We, for one, use static assignments at HE.
Owen
