Carrier Grade NAT

Owen DeLong owen at
Wed Jul 30 05:22:24 UTC 2014

On Jul 29, 2014, at 4:13 PM, Mark Andrews <marka at> wrote:

> In message <20140729225352.GO7836 at>, Matt Palmer writes:
>> On Wed, Jul 30, 2014 at 09:28:53AM +1200, Tony Wicks wrote:
>>> 2. IPv6 is nice (dual stack) but the internet without IPv4 is not a viable
>>> thing, perhaps one day, but certainly not today (I really hate clueless
>>> people who shout to the hills that IPv6 is the "solution" for today's
>>> internet access)
>> Do you have IPv6 deployed and available to your entire customer base, so
>> that those who want to use it can do so?  To my way of thinking, CGNAT is
>> probably going to be the number one driver of IPv6 adoption amongst the
>> broad customer base, *as long as their ISP provides it*.
> Add to that over half your traffic will switch to IPv6 as long as
> the customer has a IPv6 capable CPE.  That's a lot less logging you
> need to do from day 1.

That would be nice, but I’m not 100% convinced that it is true.

Though it will be an increasing percentage over time.

Definitely a good way of reducing the load on your CGN, with the additional benefit
that your network is part of the solution rather than part of the problem.

>>> 3. 99.99% of customers don't notice they are transiting CGNAT, it just
>>> works.
>> More precisely: you don't hear from 99.99% of customers, regardless of
>> whether or not they notice problems that are caused by CGNAT.  People put up
>> with some *really* bad stuff sometimes without mentioning it to their
>> service provider.
> Like modems that introduce 2 second queuing delays the moment you
> have a upstream transfer like a icloud backup.  Buffer @!#[email protected]#$!
> bloat!

Among other things.

99.99% of customers don’t now how to isolate the fault of such a thing to their ISP or how to properly complain about it in my experience. For the 0.01% who do, 99% of them don’t know how to get past the ISP’s first-line “let’s reboot your modem and when you call back afterwards, you won’t be my problem any more”.


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