运行-CMD，输入：
tracert www.baidu.com
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C:\Documents and Settings\Zhaoningbo>tracert www.baidu.com
Tracing route to www.a.shifen.com [61.135.169.125]
over a maximum of 30 hops:
1 1 ms <1 ms 1 ms localhost [10.0.2.254]
2 1 ms <1 ms <1 ms localhost [10.0.0.1]
3 2 ms 2 ms 2 ms 124.205.7.193
4 * 2 ms 2 ms localhost [172.30.33.1]
5 2 ms 3 ms 1 ms 218.247.178.37
6 9 ms 1 ms 1 ms 218.241.239.113
7 1 ms 2 ms 2 ms 124.207.222.149
8 1 ms 2 ms 3 ms 202.99.1.141
9 2 ms 2 ms 2 ms 202.99.57.145
10 26 ms 25 ms 25 ms 211.99.57.33
11 22 ms 23 ms ^C
C:\Documents and Settings\Zhaoningbo>ping 124.205.7.193
Pinging 124.205.7.193 with 32 bytes of data:
Reply from 124.205.7.193: bytes=32 time=3ms TTL=253
Reply from 124.205.7.193: bytes=32 time=2ms TTL=253
Reply from 124.205.7.193: bytes=32 time=2ms TTL=253
Ping statistics for 124.205.7.193:
Packets: Sent = 3, Received = 3, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 2ms, Maximum = 3ms, Average = 2ms
Control-C
^C
C:\Documents and Settings\Zhaoningbo>
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tracert命令的反馈结果中，第2行为网关，第3行为本地的公网IP。
需要说明的是tracert可能会出现很多*号，具体原因看网络质量吧。