aha, you can add some fiedds in your message to index the order of the pkt1, pk2,..., and the totle number of the packets. If you use TCP protocl, then you don't worry the miss the packet.

because you use listenSocket.Create(0,SOCK_STREAM) create listen socket, "0" means the server listen port is random number. this random number is also shown in the "netstat -a" list. If you use listenSocket.Create(8000,SOCK_STREAM), the listen socket port will be fixed 8000. try "netstat -a" command you will find the listen port is 8000.