TARPIT seems to work. I'm using it on 445, 135 and 135 in lieu of DROP. How can I test to determine the effectiveness in terms of how long connections are held? The tethereal output looks promising: 312.118168 68.236.182.104 -> 192.168.0.31 NBSS [TCP Retransmission] NBSS Continuation Message 312.118269 192.168.0.31 -> 68.236.182.104 TCP [TCP ZeroWindow] [TCP Dup ACK 442#3] microsoft-ds > 4969 [ACK] Seq=1 Ack=1 Win=0 Len=0 314.855014 68.236.182.104 -> 192.168.0.31 TCP [TCP Retransmission] 4902 > microsoft-ds [FIN, ACK] Seq=1 Ack=1 Win=64320 Len=0 318.134344 68.236.182.104 -> 192.168.0.31 NBSS [TCP Retransmission] NBSS Continuation Message 318.134441 192.168.0.31 -> 68.236.182.104 TCP [TCP ZeroWindow] [TCP Dup ACK 442#4] microsoft-ds > 4969 [ACK] Seq=1 Ack=1 Win=0 Len=0 BTW, has anyone compared effectiveness to La Brea?