Re: [BEHAVE] p2p applications using STUNT and EIM NATs for TCP

"Tirumaleswar Reddy (tireddy)" <> Fri, 21 June 2013 02:32 UTC

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From: "Tirumaleswar Reddy (tireddy)" <>
To: "Dan Wing (dwing)" <>, "" <>
Thread-Topic: [BEHAVE] p2p applications using STUNT and EIM NATs for TCP
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Date: Fri, 21 Jun 2013 02:32:17 +0000
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Subject: Re: [BEHAVE] p2p applications using STUNT and EIM NATs for TCP
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Another example would be ICE support for TCP using simultaneous-open between ICE TCP candidates exchanged in offer/answer.

From: Dan Wing (dwing)
Sent: Thursday, June 20, 2013 9:20 AM
Cc: Behave
Subject: Re: [BEHAVE] p2p applications using STUNT and EIM NATs for TCP

On Jun 18, 2013, at 10:25 AM, ivan c <<>> wrote:


Does any of you has examples of applications that use a STUNT server together with an EIM NAT for TCP?

This is the single purpose (besides the convenience of the implementation) of having an EIM NAT in the first place: performing port prediction with the help of a STUNT server.
I don't think you mean 'port prediction' where the software is trying to guess the next-used port ("predicting"), but I believe you mean learning the external IP address and TCP port (by talking to a TCP server on the Internet) and communicating that learned address/port to a rendezvous server of some kind (DNS server, SIP server, game server, whatever).

Surprisingly, I am not aware of any applications that rely on that. All the p2p applications that I know of use different techniques for TCP Hole Punching or use other alternatives, such as UPnP, port forwarding, etc.
I found this discussion of folks utilizing TCP hole punching (as I summarized above) for their projects,


It would be important to somewhat quantify the usage of this technique in the wild.


Ivan Chollet
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