Re: vb.net and sockets bug?

Hello,

1. Why are you creating the sockets two times?

2. Add a txSocket.Bind(new IPEndPoint(IPAddress.Any), 1234)

This will bind the socket to the local port 1234, and should solve your issue.

Best regards,
Henning Krause

"bucrepus" <bucrepus@xxxxxxxxxxxxxxxxxx> wrote in message news:%23OyWsVTdHHA.2088@xxxxxxxxxxxxxxxxxxxxxxx
Dim UpdateIP As IPAddress
Dim packet(2) As Byte
Dim txSocket As Socket = New Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
'load some data of some sort
packet(0) = 1 : packet(0) = 1
UpdateIP = IPAddress.Parse("192.168.0.100")
txSocket = New Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
Dim txPLCEP As New IPEndPoint(UpdateIP, 9001)
txSocket.SendTo(packet, txPLCEP)
txSocket.Close()
txSocket = Nothing

'packet is transmitted to 192.168.0.100 with a source dest port of 9001 and a source send port of 2039. Depending on the machine I test this code
on the source send port randomly changes around the 2000 range. verified with 2 diff packet sniffers including W2k3 server net monitor.

Thanks..
N\BUC




"buc" <bucrepus@xxxxxxxxxxxxxxxxxx> wrote in message news:uBnKlcKdHHA.2068@xxxxxxxxxxxxxxxxxxxxxxx
Why does VB.NET UDP sockets send data on random ports?. If I set a simple socket up to transmit a UDP packet on a port, look at the packet with a sniffer, the actual packets source port and dest.port are diff. The packets destination port is correct, but the packets source port it is actually sent from is random. Why? How can I figure out the actual source port windows is using, not what the vb.net socket is fake reporting?
Thanks BUC





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