中国钟学我术大草 信息网给与协议 UKIVERIT背OP SCIENC建D TECHNOLOOY O年Ca框N Direction Fields Old Values New Values Out 源P地址：协议：源端口号 10.0.0.3:TCP:2000 202.38.75.11:TCP:2000 In 目的1P地址：协议：目的端口号202.38.75.11：TCP:2000 10.0.0.3:TCP:2000 Out 源P地址：协议：源端口号 10.0.0.2:TCP:2000 202.38.75.11:TCP:2010 In 目的IP地址：协议：目的端口号202.38.75.11：TCP:2010 10.0.0.2:TCP:2000 Internet刀 Web server 10.0.0.1 响应发往 <10.0.0.2,2000>map to 202.38.75.11:2000 <202.38.75.11,2010> 10.0.0.254 10.0.0.2 将202.38.75.11：2000 转换为10.0.0.3：2000 10.0.0.3信息网络与协议 Internet 10.0.0.254 10.0.0.3 10.0.0.2 10.0.0.1 Web server a b c NAT 响应发往 202.38.75.11:2000 将202.38.75.11: 2000 转换为 10.0.0.3:2000 Out 源IP地址：协议：源端口号 10.0.0.3:TCP:2000 202.38.75.11:TCP:2000 Direction Fields Old Values New Values In 目的IP地址：协议：目的端口号202.38.75.11:TCP:2000 10.0.0.3:TCP:2000 Out 源IP地址：协议：源端口号 10.0.0.2:TCP:2000 202.38.75.11:TCP:2010 In 目的IP地址：协议：目的端口号202.38.75.11:TCP:2010 10.0.0.2:TCP:2000 <10.0.0.2, 2000> map to <202.38.75.11,2010>