Re: polling

To find out if packet are being dropped the easiest way is to create a
script and poll netstat. Correlate the netstat info with a simple
monitor program to monitor UDP packets... netstat will tell you if
packets are being dropped at socket level whereas the monitor program
will tell you what packets are being received and to which ports at
data link level.

Of course if you already know which UDP port to monitor in advance you
dont need netstat.

To write the monitor program to monitor data link level packets (at
ethernet level for example) use WinPcap for windows, or libpcap for
unix/linux. You will have to do some programming though. At source code
level, you can mix socket programming with libpcap and winpcap calls.

hope this helps
Rene

Michael Schnell wrote:
If I can find if packets are being dropped at the specific port, my
purpose would be solved.

What do you mean by "packets being dropped at the specific port" ? If a
packet gets lost in the transport, the receiving port/machine sees
nothing of it and the sending port/machine never knows that it did not
reach the destination. So there is _no_ way to detect the loss. (Unless
a higher protocol is established that performs a handshake. But this is
not "UDP" but something that _uses_ UDP).

-Michael

.

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