https://stackoverflow.com/questions/14388706/how-do-so-reuseaddr-and-so-reuseport-differ
幫助TCP打洞
C:\Users\mm>netstat -nao|findstr 16606
TCP 192.168.0.43:16606 111.19.227.19:80 ESTABLISHED 26676
TCP 192.168.0.43:16606 111.19.244.92:80 ESTABLISHED 26676
一條是和位於外網的ID中心連接,作爲控制鏈路
一條是和另一個內網機連接,作爲P2P鏈路