Re: Verizon DSL moving to CGN

[Owen DeLong <owen () delong com>]

On Apr 7, 2013, at 00:31 , Mikael Abrahamsson <swmike () swm pp se> wrote:

> On Sun, 7 Apr 2013, Fabien Delmotte wrote:
>
> > CGN is just a solution to save time, it is not a transition mechanism through IPv6
> > At the end (IPv6 at home) you will need at list :
> > Dual stack or NAT64/ DNS64
>
> CGN doesn't stop anyone deploying dual stack. NAT64/DNS64 is dead in the water without other mechanisms (464XLAT or 
> alike).

True... But... Resources deploying/maintaining all of these keep IPv4-limping along technologies are resources taken 
away from IPv6 deployment.

> My point is that people seem to scoff at CGN. There is nothing stopping anyone putting in CGN for IPv4 (that has to 
> be done to handle IPv4 address exhaustion), then giving dual stack for end users can be done at any time.

Not really...

> Face it, we're running out of IPv4 addresses. For basic Internet subscriptions the IPv4 connectivity is going to be 
> behind CGN. IPv6 is a completely different problem that has little bearing on CGN or not for IPv4. DS-Lite is also 
> CGN, it just happens to be done over IPv6 access. MAP is also CGN.

No, it really isn't. Sufficient IPv6 deployment at the content side would actually allow the subscriber side to be IPv4 
or dual-stack for existing customers with new customers receiving IPv6-only. The missing piece there is actually the 
set-top coversion unit for IPv4-only devices. (Ideally, a dongle which can be plugged into the back of an IPv4-only 
device with an IPv6-only jack on the other side. Power could be done a number of ways, including POE (with optional 
injector), USB, or other.

> I'm ok with people complaining about lack of IPv6 deployment, but I don't understand people complaining about CGN. 
> What's the alternative?

IPv6 deployment _IS_ the alternative. They are not orthogonal.

Owen