Re: Android (lack of) support for DHCPv6

[Lorenzo Colitti <lorenzo () colitti com>]

On Wed, Jun 10, 2015 at 10:25 PM, George, Wes <wesley.george () twcable com>
wrote:

> The reality is that this whole argument is needlessly conflating multiple
> things in a way that isn't helpful, so I'm going to try to break this into
> pieces in order to make forward progress and try to get us away from what
> is devolving into a debate that is equal parts religion and kool-aid
> drinking contest among IPv6 übernerds.

Thank you for trying to reword what I tried to express. Your assessment
pretty much matches mine, except for the conclusion (see below).


> So what this means is that there is a draft to be written about the need
> for multiple address support on IPv6 networks for mobile devices,
> enumerating the ways that they use those multiple addresses, and how it
> differs from today's IPv4-only or dual-stack implementations, along with a
> big discussion on the breakage that can happen on IPv6-only networks if a
> device can't get the addresses it needs. It is a fool's errand to assume
> that we can dictate one and only one solution to #5 (regardless of one's
> perceived influence and market power), so the best we can do is to
> document the preferred one(s) and hope that we've made a good enough case
> or made them easy enough to use that the majority of network operators do
> support them.
> Sunset4 is the right place for that draft, so let's discuss it at the next
> IETF.

Yep (but perhaps in v6ops instead of sunset4, see below).


> However, the spectre of #4 does NOT mean that DHCPv6 is unusable because
> it would break things today on a dual-stack network, so you need to stop
> trying to imply that, and stop trying to optimize for use cases that you
> yourself admit basically don't exist today by blocking support for
> something that we could use today to have more devices using IPv6, were it
> available.

I disagree with this part of the conclusion. I don't think it's a good plan
to implement stateful DHCPv6 now and postpone the solution of the problem
until IPv4 goes away many years from now. By then, a lot of water will have
flowed under the bridge by then, and a lot of one-address-only networks
will have been deployed and have moulded industry thinking.

So, much as it pains me to stand in the way of IPv6 adoption - and you
should how much I've tried to do on that front - I think that that wide
deployment of one-address-per-device IPv6 might actually do more harm than
good, and I expect that many operators who are going to require stateful
DHCPv6 addressing are going to use it for one-address-per-device IPv6.

I really think it's better if we get this right now, not kick the can down
the road. That means we as an industry need to find a solution for IPv6
deployment in university/enterprise networks that does not devolve into
one-address-per-device IPv6, *before* one-address-per-device IPv6 becomes
universally implemented and usable.