Common operational misconceptions

Masataka Ohta mohta at
Fri Feb 17 02:07:59 UTC 2012

Valdis.Kletnieks at wrote:

>> While NAT breaks the end to end connectivity, it can be
>> restored by end systems by reversing translations by NAT,
>> if proper information on the translations are obtained
>> through some protocol such as UPnP.
> You got a front end NAT.  You got 3 boxes behind it that all
> want to listen for inbound connections on port 49734.
> Let me know how that works out for you.

It's just like your box can't listen for inbound connections
at address (address of my box).

However, if UPnP box is configured properly, your box behind
it can listen for inbound connections on some ports at some
public address.

Issues on stability and advertisements of the port numbers
are not very different from those of addresses, which may
be assigned by DHCP.

					Masataka Ohta

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