I currently have Time Warner Cable Wideband Internet service. This uses a SMC Cable Modem (Model SMCD3GN).
If I plug my MacBook directly into the cable modem via Ethernet and restart it, I get an IP address in the 72.227.xxx.xxx range.
If I plug my AirPort Extreme router into the cable modem via Ethernet and restart it, I get an IP in the 24.193.xxx.xxx range.
Why does Time Warner change the IP range depending on which device I plug in, and how does the cable modem know that a different type of device has been connected to the cable modem?
Also, I seem to get much better performance on the 72.227.xxx.xxx range than 24.193.xxx.xxx - I can only speculate that perhaps a different set of routers/switches is handling each range?