Due to the scarcity of IPV4 addresses, general home users and small companies are sharing the same extranet IP, IP and local IP, a very simple way to view the Internet IP is to open Baidu, direct search "IP address" will be able to look at your network of Internet IP, the following screenshot.
How to replace your own extranet IP?
We need to use the agent IP to replace their own IP, can be in the West Thorn free agent IP, quick proxy to get free agent IP, of course, there are many, specific can be Baidu.
Next use IE9 as a demo, such as I get a free proxy IP: 202.106.169.142 port is: 80, open IE settings->internet option-> connection-> LAN settings-> for LAN use proxy server hook, and fill in our obtained proxy IP and port-> last click OK save, steps as follows screenshot.
Finally see if your extranet IP has been replaced successfully