Seamless mobility requirements and mobility architectures

All layers of the OSI stack affect seamless mobility either directly or indirectly. We discuss different possible IP mobility architectures. We compare the architectures and provide some insight based on our experience with two of these technologies. We identify several problems which remain in achieving seamless mobility: application session persistence, integration with other technologies like IP multicast and real-time streaming media, and seamless handoff between different access networks (wireless personal area networks (PANs), local area networks (LANs) and wide area networks (WANs))