CGNAT Solutions

Robert Blayzor rblayzor.bulk at
Wed Apr 29 14:13:38 UTC 2020

On 4/28/20 11:01 PM, Brandon Martin wrote:
> Depending on how many IPs you need to reclaim and what your target
> IP:subscriber ratio is, you may be able to eliminate the need for a lot
> of logging by assigning a range of TCP/UDP ports to a single inside IP
> so that the TCP/UDP port number implies a specific subscriber.
> You can't get rid of all the state tracking without also having the CPE
> know which ports to use (in which case you might as well use LW4o6 or
> MAP), but at least you can get it down to where you really only need to
> log (or block and dole out public IPs as needed) port-less protocols.

I'm wondering if there are any real world examples of this, namely in
the realm of subscriber to IP and range of ports required, etc.  ie: Is
is a range of 1000 ports enough for one residential subscriber? How
about SMB where no global IP is required.

One would think a 1000 ports would be enough, but if you have a dozen
devices at home all browsing and doing various things, and with IOT,
etc, maybe not?


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