Brandon Martin wrote:

>> If you mean getting rid of logging, not necessarily. It is enough if
>> CPEs are statically allocated ranges of external port numbers.
>
> Yes, you can get rid of the logging by statically allocating ranges of
> port numbers to a particular customer.

And, that was the original concern.

> What I was referring to, though, was the programmatic state tracking of
> the {external IP, external port}-{internal IP, internal port} mappings.

OK.

>   You can't eliminate that unless the CPE also knows what internal port
> range it's mapped to so that it restricts what range it uses.  If you
> can do that, you can get rid of the programmatic state tracking entirely
> and just use static translations for TCP and UDP which, while nice, is
> impractical.  You're about 95% of the way to LW4o6 or MAP at that point.

Interesting. Then, if you can LW4o6 or MAP, you are about 95% of the
way to E2ENAT with complete end to end transparency using IPv4 only,
which means we don't need IPv6 with 4to6 NAT lacking the transparency.

        https://tools.ietf.org/html/draft-ohta-e2e-nat-00

                                                Masataka Ohta