Cablewifi / xfinitywifi technical notes

June 27, 2016

xfinitywifi is one of the most widespread Wifi SSIDs in the USA. It’s not just limited to Xfinity cable internet subscribers; other cable companies partner their subscribers in or paid access is available.

Like most WiFi captive portals, xfinitywifi uses the device MAC address like a “cookie” after the web browser login. For devices without a web browser, a more capable device might sign in once with the non-browser device’s MAC.

xfinitywifi has the usual range limits of 2.4 GHz and 5 GHz Wifi. xfinitywifi is a VLAN-like network, separated from host subscriber network. The maximum distance from the WiFi router depends on the Xfinity router placement. For example, one might pickup the router in an adjoining building or dwelling. Coverage maps are notional, and don’t account for building materials or interference.