"It's the end of the world as we know it" -- REM

Thu Apr 25 18:09:41 UTC 2013

On Apr 25, 2013, at 11:24 AM, Michael Thomas <mike at mtcc.com> wrote:

> So here is the question I have: when we run out, is there *anything* that
> will reasonably allow an ISP to *not* deploy carrier grade NAT? Assuming
> that it's death for the ISP to just say no to the long tail of legacy v4-only
> sites?

This assumes facts not in evidence. However, given that assumption, it's
not so much a question of whether to CGN, but how. It looks like it may
be far better, for example, to do something like 464xlat with an all IPv6
network than to run dual-stack with NAT444 or DS-LITE.

There's no shortage of possible ways to run IPv4 life support, but they're
all life support. You have all the same risks as human life support…

Intracranial pressure, diverse intravascular coagulopathy (DIC),
stroke (CVA), embolisms, etc. In the network, we refer to these
as router instability, state table overflow, packet loss, bottlenecks,
etc.

Other options include NAT64/DNS64, A+P, etc.

Bottom line… The more IPv6 gets deployed on the content side, the less
this is going to hurt. Eyeballs will be forced to deploy soon enough. It's
content and consumer electronics that are going to be the most painful
laggards.

> One thing that occurs to me though is that it's sort of in an ISP's interest
> to deploy v6 on the client side because each new v6 site that lights up on
> the internet side is less traffic forced through the CGN gear which is ultimately
> a cost down. So maybe an alternative to a death penalty is a molasses penalty:
> make the CGN experience operable but bad/congested/slow :)

That latter requires no additional effort beyond merely deploying CGN. ;-)

Owen