Quasi mobile IP-based architecture for seamless interworking between WLAN and GPRS networks

Fixed local service and cellular operators around the world have shown interest in providing wireless local area network (WLAN) services to their subscribers together with traditional packet data cellular services in a hybrid infrastructure in which subscribers can roam seamlessly. This document specifies the system description for a seamless interworking between a general packet radio service (GPRS) system and a wireless local area network. The main objective is to extend the services available in IP networks (e.g. Internet) providing session persistence to both cellular packet data network subscribers and WLAN users. A quasi mobile IP architecture is proposed as a suitable solution together with a network discovery and roaming algorithm. The proposed framework allows for independent system engineering, reuse of current infrastructure, charging, robustness and security. A new node is introduced called home agent and minimal changes on MN software providing the necessary seamless interconnection capability to any user which owns a terminal with GPRS and WLAN interfaces as well as valid credentials to access both networks.