CGNAT Solutions

james jones james.voip at
Wed Apr 29 14:28:19 UTC 2020

How big is your ip pool for CGNAT?

On Wed, Apr 29, 2020 at 10:17 AM Robert Blayzor <rblayzor.bulk at>

> 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?
> --
> PGP:
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