method to find my UDP socket's "real" port?

Posted by yairchu on Stack Overflow See other posts from Stack Overflow or by yairchu
Published on 2009-08-03T16:17:11Z Indexed on 2010/05/09 3:58 UTC
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Filed under:

udp

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nat

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p2p

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sockets

Is there any free service to which I could send a UDP packet and it would respond telling me what is my "real" UDP port? (my application is behind a NAT)

This kind of service could allow me to make a p2p coordination server with normal php hosting.

The p2p clients would know their UDP ports from this service
They will then contact my server over HTTP (which is what regular web hosting allows) and tell it their port (and ip, which is normally supplied to cgi scripts)
My server will give the clients the IP addresses and ports of the other clients.

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