[186984] in North American Network Operators' Group
Re: IPv6 Implementation and CPE Behavior
daemon@ATHENA.MIT.EDU (James R Cutler)
Mon Jan 11 20:19:40 2016
X-Original-To: nanog@nanog.org
From: James R Cutler <james.cutler@consultant.com>
In-Reply-To: <3C7A85BE-821B-4EA7-AF74-D2B707346FED@delong.com>
Date: Mon, 11 Jan 2016 20:19:32 -0500
To: Owen DeLong <owen@delong.com>
Cc: North American Network Operators' Group <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
> On Jan 11, 2016, at 1:37 PM, Owen DeLong <owen@delong.com> wrote:
>=20
>=20
>> On Jan 11, 2016, at 10:23 , James R Cutler =
<james.cutler@consultant.com> wrote:
>>=20
>>> On Jan 11, 2016, at 12:01 PM, Graham Johnston =
<johnstong@westmancom.com> wrote:
>>>=20
>>> Are most CPE devices generally not IPv6 capable in the first place? =
For those that are capable are they usually still configured with IPv6 =
disabled, requiring the customer to enable it? For those CPE that are =
capable and enabled, is there a common configuration such as full blown =
DHCPv6 with PD?
>>=20
>> I can=E2=80=99t speak regarding =E2=80=9Cmost CPE devices=E2=80=9D =
but for CPE =3D Apple Airport Extreme
>>=20
>> =E2=80=A2 At least since the AirPort Extreme 802.11n =
(AirPort5,117) was released in 2011, the hardware has supported native =
IPv6 routing and acceptance of PD from the WAN.
>>=20
>> =E2=80=A2 The default configuration for firmware 7.7.3 is =
automatic WAN IPv6 configuration, native IPv6 routing, and, acceptance =
of PD from the WAN. End systems on the single LAN receive a /64.
>=20
> To be more clear=E2=80=A6 The LAN receives a /64 from which end =
systems are able to construct one or more end system addresses using =
SLAAC.
I tried to keep it simple - my original draft said =E2=80=9CAll end =
systems on the LAN receive the same /64 prefix in RAs, even if the ISP =
has delegated a /56, for example. It was altogether too wordy so I =
excised about half of the original text. Maybe I went too far.
>=20
>>=20
>> =E2=80=A2 No DHCPv6 is provided to the LAN through firmware up =
to the current version 7.7.3.=20
>>=20
>=20
> The good news is that RDNSS is allegedly supported in recent firmware =
releases.
I have found no documentation from Apple or in the Airport Utility GUI =
that mentions it. I have figured out some of IPv6 entries in .baseconfig =
files, but none for RDNSS.
The bad news is that I have yet to really understand RDNSS in the =
context of OS X. I don=E2=80=99t find any recognizable mention in sysctl =
inet6 parameters. OS X El Capitan systems autoconfigure the =
LAN/64:EUI-64 address of the Airport Extreme along with the IPv4 =
nnn.nnn.nnn..1 address as DNS server addresses. Windows 10 appears to =
do the same. (I haven=E2=80=99t bothered to look into Windows internals. =
I don=E2=80=99t get paid to do that anymore.) I keep IPv6 disabled on =
my Snow Leopard Server instances, both because no IPv6 DNS server =
address is ever autoconfigured and because none of those instances =
should ever get incoming IPv6 traffic.
>=20
> Owen
Thanks for your comments.
James R. Cutler
James.cutler@consultant.com
PGP keys at http://pgp.mit.edu
