Tcp有以下特点
Reliable
connection oriented
byte-stream service
要处理
flow control:
要有一个机制控制传送不要让buffer溢出
congestion control:
involves preventing too much data from being injected into the network,
thereby causing router/switches or link to become overloaded
TCP sliding windows algorithm (滑动窗口)
数据收发的时候，两端都有一个buffer，当buffer满地时候再发送单位为segment