<p>234234234234</p><p>ECN<span style="font-family:宋体">的支持涉及的实体包括</span>TCP<span style="font-family:宋体">交互的</span>client<span style="font-family:宋体">和</span>server<span style="font-family:宋体">以及中间的路由器；涉及协议也包括</span>IP<span style="font-family:宋体">和</span>TCP<span style="font-family:宋体">两层。</span></p><p>Ip<span style="font-family:宋体">层在</span>DSCP<span style="font-family:宋体">字段后面两个</span>BIT,<span style="font-family:宋体">由</span>TCP<span style="font-family:宋体">发送端</span>(<span style="font-family:宋体">这个发送端包括</span>client<span style="font-family:宋体">和</span>server<span style="font-family:宋体">，只要涉及到发送数据都交发送端，比如</span>client<span style="font-family:宋体">的</span>http get<span style="font-family:宋体">等</span>)<span style="font-family:宋体">和中间路由器设置</span></p><p><img src="http://119.23.57.31:8885/test/bootstrap/ueditor/themes/default/images/spacer.gif" width="553" height="133"/></p><p>TCP<span style="font-family:宋体">层在</span>FLAG<span style="font-family:宋体">处增加了</span>ECE<span style="font-family:宋体">和</span>CWR<span style="font-family:宋体">两个表示，由</span>TCP<span style="font-family:宋体">发送和接收端设置。</span></p><p><br/></p>