[180677] in North American Network Operators' Group
Re: Android (lack of) support for DHCPv6
daemon@ATHENA.MIT.EDU (Jared Mauch)
Tue Jun 9 16:55:41 2015
X-Original-To: nanog@nanog.org
From: Jared Mauch <jared@puck.nether.net>
In-Reply-To: <alpine.DEB.2.02.1506092238130.9487@uplift.swm.pp.se>
Date: Tue, 9 Jun 2015 16:51:51 -0400
To: Mikael Abrahamsson <swmike@swm.pp.se>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
> On Jun 9, 2015, at 4:43 PM, Mikael Abrahamsson <swmike@swm.pp.se> =
wrote:
>=20
> On Tue, 9 Jun 2015, Joel Maslak wrote:
>=20
>> Agreed - apparently the solution is to implement SLAAC + DNS =
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>> *AND* DHCPv6. Because you need SLAAC + DNS advertisements for =
Android, and
>> you need DHCPv6 for Windows.
>>=20
>> Am I the only one that thinks this situation is stupid?
>=20
> You don't need to hand out addresses by means of DHCPv6 IA_NA to =
windows, it does A=3D1 mode for SLAAC just fine.
>=20
> There is a big difference between handing out resolver, ntp-server, =
dns search domains etc by means of DHCPv6, and handing out addresses =
based on DHCPv6 (stateless vs stateful).
>=20
>> =46rom what I have understood Android has made design decisions that =
means=20
> some things will break if you would only give is a single IPv6 =
address. This is most likely what some operators want to achieve when =
they say they want to use DHCPv6 IA_NA.
>=20
> In order to actually solve the problem they're trying to solve, you =
need SAVI (https://tools.ietf.org/wg/savi/) and 802.1x (or similar =
mechanism) in order to actually gain the control these people are =
looking for. My question, do they implement this on IPv4?
It=E2=80=99s way more fun to fight about it when NDP and DHCPv4 were =
coming of age at the same time, and DHCP was seen as only a minor =
upgrade to BootP at the time. The IPv6 purists seem to think that DHCP =
=3D=3D NAT =3D=3D EVIL at times which is frustrating.
The result is we have both M=3D0, M=3D1, etc.. options and something can =
be sent via NDP or DHCP, including possible DHCP-PD in conjunction.
The reality is I need things to =E2=80=9Cjust work=E2=80=9D. It was =
interesting to inherit someones half-done IPv6 implementation on our VPN =
platform, they didn=E2=80=99t understand that proxy-arp didn=E2=80=99t =
really exist in IPv6 land and the block had to be routed to the VPN box.
There are many minor and subtle differences in these technologies which =
become obvious when some time is spent digging through them.
- Jared=
