TCP/IP 详解 卷1 ch22 TCP的坚持定时器

1. 发送方必须能够处理ACK报文丢失的情况。

TCP must handle the case of this acknowledgment that opens the window being lost. Acknowledgments are not reliably transmitted-that is, TCP does not ACK acknowledgments, it only ACKs segments containing data.

 

2. 例子

服务器端在读取数据前先休眠一段时间，这时缓冲区已满，接收窗口为0。

 

客户端的的persist定时器使用了二进制退让算法。

 

3. 糊涂窗口综合症 Silly Window Syndrome

Window-based flow control schemes, such as the one used by TCP, can fall victim to a condition known as the silly window syndrome (SWS). When it occurs, small amounts of data are exchanged across the connection, instead of full-sized segments.