<p> 关于在linux下用Ethereal这个工具来分析TCP的规律， 小弟有几个问题想请教高手回答一下，救命的。谢谢感激不尽<br/>1 What happens to the size of the transmit window when a packet is lost?<br/> 当一个传送包丢失时， 传送窗口的大小如何改变？<br/>2 At what stage is the re-transmission sent, and how many packets are retransmitted when one is lost?<br/> 重新发送是在如何一个过程？ 当一个包丢失， 多少包需要重新发送？<br/>3 what is the options field in the TCP header for a duplicate acknowledgement. what is it used for?<br/> 关于TCP header的 option field <br/>4 when you download a file from a sever,Try and work out what is going on. Sketch the graph of which packets arrive when, and explain in as much detail as you can what is going on. <br/> 当你从一个服务器下载一个文件，具体发生了什么，尽可能详细<br/></p>