US Patent 6842462 Wireless access of packet based networks

A General Packet Radio Service (GPRS) Accessed Extended Mobile Internet Protocol (EMIP) [G-EMIP] network is provided for wireless mobile device access to external packet data networks. Domains are defined to incorporate a subnet of standard GPRS and EMIP network entities accessed through a Domain Router. Packet access at the radio interface is provided using the base station portion of a GPRS network. Wireless link specific processing is relegated to this potion of the G-EMIP network. EMIP is utilized as a backbone network to provide mobility and service management and interconnection to external networks. A GPRS-IP Interworking entity (GII) interworks IP and GPRS protocols between GPRS and IP addressable network entities (i.e., translates messages of each protocol to corresponding messages of the other protocol). Mobility-related functionality is handled at the IP (network) layer. Mobile IP is used to support the macro-mobility and Handoff-Aware Wireless Access Internet Infrastructure (HAWAII) is used to support micro-mobility and paging. The Domain Router provides packet service management and interacts with a Home Location Register/Authentication Center, which provides GRPS registration, authentication and encryption.