Common operational misconceptions

Valdis.Kletnieks at Valdis.Kletnieks at
Fri Feb 17 04:58:44 UTC 2012

On Fri, 17 Feb 2012 11:07:59 +0900, Masataka Ohta said:
> 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.

No, you said specifcially that it can be restored by end system*S*
plural.  Yes, I can get one box listening.  Now tell me how to get
the second and third boxes listening on the same port.  If you can't
do that, then in fact, it is *not* possible to restore *full* end-to-end
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