Design and implementation of a WLAN/cdma2000 interworking architecture

The combination of 3G and WLAN wireless technologies offers the possibility of achieving anywhere, anytime Internet access, bringing benefits to both end users and service providers. We discuss interworking architectures for providing integrated service capability across widely deployed 3G cdma2000-based and IEEE 802.11-based networks. Specifically, we present two design choices for integration: tightly coupled and loosely coupled, and recommend the latter as a preferred option. We describe in detail the implementation of a loosely coupled integrated network which provides two kinds of roaming services, a SimpleIP service and a Mobile-IP service. We present, in detail, two new components used to build these services: a network element called a WLAN integration gateway deployed in WLAN networks; a client software on the mobile device. For a mobile device with interfaces to both technologies, our system supports seamless handoff in the presence of overlapping radio coverage.