Techniques are provided to support roaming of wireless devices in a network such that the wireless devices can keep their Internet Protocol (IP) addresses as they roam within and across mobility sub-domains. When a wireless device roams from one access switch to another access switch, a tunneling endpoint apparatus in the wireless device's home mobility sub-domain is configured to serve as the point of presence for the roamed wireless device. Traffic for the roamed wireless device is tunneled from the access switch where the wireless device has roamed (where it is currently attached) to the tunneling endpoint apparatus. When the wireless device roams across mobility sub-domains, then traffic is tunneled from the access switch where the wireless device is currently attached to the tunneling endpoint apparatus in that mobility sub-domain (called a “foreign” mobility sub-domain) to the tunneling endpoint apparatus in the wireless device's home mobility sub-domain.