NetDump.exe is used to capture packets just like WinPcap. PacketInjecter.exe is used to send a TCP sync packet. Put the two exe files in the x86 folder, which contains the necessary dlls. The commands are as follows: Test Case 1 (two commands run in the same machine, if 3389 port is opened, the system will reply by using a SYN&ACK packet): NetDump.exe "tcp and (ip.DstAddr == 127.0.0.1 and ip.SrcAddr == 127.0.0.1 and (tcp.DstPort == 3389 or tcp.SrcPort == 3389))" PacketInjecter.exe 127.0.0.1 127.0.0.1 3389 Test Case 2 (two commands run in the same machine, if 11111 port is NOT opened, the system will reply by using a RST&ACK packet): NetDump.exe "tcp and (ip.DstAddr == 127.0.0.1 and ip.SrcAddr == 127.0.0.1 and (tcp.DstPort == 11111 or tcp.SrcPort == 11111))" PacketInjecter.exe 127.0.0.1 127.0.0.1 11111 Test Case 3 (NetDump.exe run in 192.168.1.158, PacketInjecter.exe run in 192.168.1.232): NetDump.exe "tcp and ((ip.DstAddr == 192.168.1.232 or ip.SrcAddr == 192.168.1.232) and (tcp.DstPort == 80 or tcp.SrcPort == 80))" PacketInjecter.exe 192.168.1.232 192.168.1.158 80 Test Case 4 (NetDump.exe run in 192.168.1.158, PacketInjecter.exe run in 192.168.1.232): NetDump.exe "tcp and ((ip.DstAddr == 192.168.1.232 or ip.SrcAddr == 192.168.1.232) and (tcp.DstPort == 11111 or tcp.SrcPort == 11111))" PacketInjecter.exe 192.168.1.232 192.168.1.158 11111