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Unread 10-08-2009, 11:41 AM   #6
boatman
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Quote:
Originally Posted by wahran View Post
how would you test UDP if you have no control over the other end, is there a way? I am under the impression that you send your UDP packet and it's gone (no ack...etc).
Using nmap and Wireshark I sent some UDP packets on port 4060. I observed that when there is no service running on that port then an "ICMP Destination unreachable" packet is returned, but if there is a service then no packet is returned.

nmap -P0 -sU -p4060 us.voxalot.com
no packet was returned

nmap -P0 -sU -p4040 us.voxalot.com
ICMP Destination unreachable" packet was returned because us.voxalot.com does not use UDP port 4040.

nmap -P0 -sU -p4060 proxy01.sipphone.com
ICMP Destination unreachable" packet was returned because proxy01.sipphone.com does not use UDP port 4060.
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