Seamless Mobility over Broadband Wireless Networks
A broadband wireless architecture with 802.11 (WLAN/WiFi) as a core coverage technology supported by 3G cellular (UMTS) as additional coverage for signaling and umbrella functionality is presented in this paper. The backbone network is wired and the individual broadband subscribers maintain a so called Residential Gateway (RG) which technically allows the splitting of the wireless access network provided by each residential WLAN access point into two virtual networks; one private for the RG owner and one for visiting users who roam in the vicinity of the access point. The mobile visiting users thus roam between the publicly accessible WLAN networks maintaining their session and service connectivity as they move between residential WLAN coverage areas. Both residential and visiting users are served by an architecture that provides separation between traffic types, management of quality of service, security and seamless mobility. Users are automatically authenticated and service continuity is maintained as the user moves between coverage areas. The focus of this paper is on technical aspects which enable seamless mobility and automatic authentication of users in a way which is even transparent to the applications running on their multimode mobile devices.