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I have some hardware on my internal network which I want to send udp packets. I can connect using telnet to it prooving that TCP and port forward works but when I try to send a UDP packet externally it fails.

I can however send the same packet internally and port forwarding works fine.

My router is Linksys by Cisco WAG320n.


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what sort of datagram is it? if it's broadcast or multicast, that doesn't work over NAT/outside the LAN/switched network. ;) when you have the forwarding rule set up in the web interface, you can confirm that the protocol is set to "Both" and not just "TCP", right? –  brent saner Dec 5 '11 at 12:47
It is a java.net.DatagramSocket and sending DatagramPacket –  user103122 Dec 5 '11 at 17:29

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