UDP Broadcast datagrams sent and received on same computer.

[riaancillie]

I apologize in advance since this isn't strictly the most appropriate
group to ask this question in.

I am using a Socket to broadcast UDP datagrams as such:

FSocket.EnableBroadcast = true;
FSocket.SendTo(bytes, new IPEndPoint(IPAddress.Broadcast, 9991) );

I receive the datagram on the other computers on the network, but the
computer sending the datagram does not receive the packet. Is this
normal behaviour? I.e Are broadcast packets received by a network
interface ignored if it realizes it was also the sender?

Incidentally, if I open Ethereal/Wireshark and start capturing
packets, the problem disappears and all broadcast packets are suddenly
received by the sending computer as well.

 

[riaancillie]

Thanks, switching the card into promiscuous mode did allow me to
receive the messages, but none of the other computers were unable to
receive broadcast packets they sent themselves. I started looking for
network filters in the registry etc. and stumbled across Kaspersky
Anti-Virus NDIS Filter. After disabling it and restarting the network
card, everything was back to normal.