http://www.52im.net/thread-1939-1-1.html
理解TCP/IP 网络栈 https://cizixs.com/2017/07/27/understand-tcp-ip-network-stack/
[书] tcp/ip详解 卷1 http://www.52im.net/topic-tcpipvol1.html
kenel TCP/ip https://my.oschina.net/u/4106059/blog/3037529